Latest update 5/30/2010 - "brands" tested: 22, "models" tested: 72. As far as I am concerned, 2 of these 72 appear to me to be good.
General Descriptions, including color and spectrum
Bug Reports
65 of the tested 72 "models" tested claimed to replace or be equal to incandescents of anywhere from 40 to 150 watts, 60 of those claimed to replace or be equivalent to incandescents of wattage 50-125 watts, and only two of these 72 in my tests outshone better 40 watt "standard" incandescent lightbulbs.
UPDATE 7/6/2009: I have tried several different dollar store CFLs with a "Kill-A-Watt" wattmeter to measure power consumption. They mostly consume 9 watts or a little less, even if nominal wattage is as high as 26 watts. Only one that I measured power consumption of so far consumed more than 11 watts.
47 of 72 "models" that I tested were of "quadtube" type, and two of those had glass outer bulbs around them. I have seen 19 spirals of "dollar store brands" in dollar stores for $1-$2. I have seen spirals for $3 in a small number of dollar stores, but so far I do not consider those to be "dollar store" compact fluorescents" but something better than these. 6 other "dollar store" models tested were tripletwintubes.
Nearly all that I have seen so far came in packages saying "energy saving light bulb" or "energy saving bulb" or "energy saving lamp".
UPDATE 12/17/2006: These largely lack the UL listing and the required FCC ID that other 120 volt AC compact fluorescents having integral electronic ballasts normally have if marketed in the USA. The Capitol Electric ones are an exception, having the UL symbol and a listing number "6G59" and "FCCIDNQXPL".
These are now organized into seven sections:
* Better dollar store models from Dollar Tree (new section 2/21/2010).
* "cool daylight" quadtube (most dollar store ones) - many say "warm white" or
"sun lighting" or "natural soft white light" (updated 2/17/2008).
* A slightly better "cool daylight" quadtube dollar store model - "TOOLMART"
"25 watt"
* Similar but actually "warm white" versions of these (updated 9/10/2006)
* Capitol Electric 11 watt warm color models
* Spiral models (new category 7/31/2005, UPDATED 11/5/2007)
* Tripletwintube models (new category 8/4/2005, UPDATED 3/30/2008)
Better models available at Dollar Tree I have seen two so far. I have seen in operation, and remember the brand and wattage of, only one model so far. It was a Sunbeam 11 watt doubletwintube. That was not one I purchased, but one that a friend of mine has and claimed to have purchased for one dollar at Dollar Tree.
I did not see it at the Dollar Tree closest to where I live.
It appears to me better than the 20 brands that I see mainly at dollar stores other than Dollar Tree and that I have not seen at Dollar Tree. Light output is claimed to be 570 lumens (if I remember correctly). Light output appears to me to be close to what is claimed. The color is a warm incandescent-like color with color temperature around 2600 K. The spectrum indicates color rendering index close to the usual 82 of non-dollar-store CFLs.
UPDATE 5/30/2010: I recently found the other one of these at the Dollar Tree closest to where I live. It is a 13 watt Greenlite spiral. The package claims life expectancy of 12,000 hours, 950 lumens of light output, and has the Energy Star logo. My testing indicates light output around 900-950 lumens, so I consider this claim to be accurate. The color is extremely slightly pinkish in comparison to an incandescent. The spectrum is a usual one indicating color rendering index of 82.
This one has cULus and FCC logos and UL listing/file numbers 53SJ and E176533.
The "cool daylight" quadtubes
A wide variety of dollar store "brands" of compact fluorescents are so similar (I believe possibly identical and possibly from the same factory) that I have decided to lump them together here. These come mostly in nominal wattages of 11, 13, 15, 18, 20 and 25 watts, sometimes 9, 26 and 36 watts. The main difference among these "wattages" is a minor variation in size. All appear to have power consumption generally around 7-11 watts (revised downward from 9-13 watts 7/6/2009 after using a wattmeter rather than estimating heat output). All have light output that I estimate to be around 300-400 lumens, mostly closer to 400 lumens, except the "Sun Lighting" "36 watt" and the Sonitech "20 watt" were slightly brighter, maybe 400-450 lumens. This is brighter than 25 watt incandescents but dimmer than 40 watt "standard" incandescents. All had a "daylight" bluish white color, with color temperature ranging from approx. 6500 to approx. 8000 Kelvin. Some had a rated color temperature of 6400 Kelvin.
The spectrum is favorable enough to night vision to, in some situations, (such as outdoors at night) give an "illuminating power" like that of 40 watt incandescents or maybe sometimes even the dimmer, longer life variations of 60 watt incandescents.
Depending on the "nominal wattage", with few exceptions these are claimed to replace incandescents of wattage anywhere from 50 to 125 watts.
Some of these come in packages saying "SUN Lighting".
The spectrum of these is like that of "Daylight" fluorescents, which have a color rendering index in the upper 70's. Some, especially of the "The Brightest" "brand", have the spectrum having in addition a trace of the features of triphosphor formulation, but not enough to significantly affect the color rendering properties.
BRANDS/MODELS in this group with icy cold bluish light:
Cixing - 20 watt T110-20W-100ATT, 25 watt T110-25W-125ATT
Hongyao - 25 watt.
Lumilar - 13 and 25 watts
My Products "SUN Lighting" - 15, 20, 25 watts
Pride - 20 watts
Sonitech - 20 watts, claimed to produce 1580 lumens
Sparkling - "13 watt" HW-2301, "15 watt" HW-2302, "20 watt" HW2303
"SUN LIGHTING" - 20 watts "SOFT WARM WHITE", 25 watts "SOFT WARM
WHITE", "36 watts" (slightly brghter than most in this class but still not
outshining 40 watt "standard" incandescent.)
Telstar - 11, 13, 15, 18, 20 watts. Model numbers include "LB-11",
"LB-13", "LB-15", "LB-18" and "LB-20", even ones in packages claiming
"Soft warm white light".
Teng Fei - 25 watts - claimed to produce 1130 lumens and to replace
a 125 watt incandescent.
The Brightest, if these have any "brand" at all, in packages saying
"natural soft white light":
13 watt model # EN13-60W, claimed to produce 865 lumens
15 watt model # EN15-75W, claimed to produce 1130 lumens
20 watt model # EN20-100W, claimed to produce 1580 lumens
UPDATE 12/30/2006: I saw in a dollar store some of these "The Brightest" ones next to some "Trisonic" ones, and the packages had a large number of similarities and few differences. The main difference was lack of "Trisonic" on the former. Both had "The Brightest" in the upper right corner in the same style of print and with the same pattern of stars.
Tool Mart - 15, 20 watts
Top "SUN Lighting" - 20 watts
Trisonic:
"9 watt" TS-EN9W-40 (claimed to produce 505 lumens),
"13 watt" TS-EN13W-60 (claimed to produce 505 lumens),
"15 watt" TS-EN15W-75 (claimed to produce 1130 lumens),
"20 watt" TS-EN20W-100 (claimed to produce 505 lumens)
All four claimed "natural soft white light".
Tyrone Imports 20 watt, item no. EL5008, a 25 watt model and a
26 watt one.
Volt Power - 11 watts
A "brand" noted only by a logo that slightly resembles the word "ACE",
20 watts
BUG REPORTS: One "13 watt" "Telstar" died after a few minutes and made
sizzling sounds, a "burning" orange glow in its base, and noticeable smoke
(mostly filling a room with smoke) in the process. A 25 watt "Hongyao", after
I used it for only roughly 10 starts and a few operating hours, upon loaning to
a friend for spectrum analysis flickered wildly and on the next start burned
out with high output of smoke and a bad burning odor. A "13 watt" "Lumilar"
flickered and was unusually dim even for "13 watt" dollar store conmpact
fluorescent bulbs. A "20 watt" "Tyrone" sometimes when cold does not start
but only glows at the ends of its tubing until I touched the tubing or wait
two minutes. A "20 watt" "Cixing" had a loose internal part in its base and
rattled when shaken, but has yet to electrically malfunction. A "20 watt" "The
Brightest" had a ballast housing that came apart. A "20 watt" "Sparkling" was
DOA. Another 20 watt "Sparkling" had an intermittent internal connection.
All that I tested produced to some extent or another less light than the
packages they come in lead me to expect, in some cases falling short by a
factor of more than 3.
"25 watt" "TOOLMART" - UPDATE 9/26/2004
A "25 watt" "TOOLMART" that I purchased at a dollar store in the summer of
2004 is noticeably slightly better than other dollar store "cool daylight"
quadtube compact fluorescents. The light output I estimated to be 400-450
lumens, which is a little more than that of most other "dollar store" compact
fluorescents and only very slightly less light than that of a "regular" 40
watt incandescent lightbulb. Although better than most other "dollar store"
"Daylight" compact fluorescents, it seriously falls short of claimed light
output - it claims to replace a 125 watt incandescent.
The spectrum of this one indicated a "triphosphor" phosphor formulation, and
compact fluorescents with this spectrum typically have a color rendering
index of 82. The color temperature was around or not much over 6500 K - same
as that of "Daylight" fluorescents. Other "dollar store" "cool daylight"
compact fluorescents vary in color from this to a slightly more blue color
that is close to 8000 Kelvin.
Actual power consumption is close to 11-12 watts (my estimate from heat output).
It is to be noted that "15 watt" and "20 watt" "TOOLMART" units had the lower light output and "daylight" (as opposed to the better "triphosphor") spectrum that most "dollar store" compact fluorescents have.
"Warm White" versons of these UPDATE 9/10/2006
There are "warm white" versions of these, of the Fieldbreeze and Sunbrite brands. Light output is similarly low - around 300 to 400 lumens for the Filedbreeze ones and close to or maybe a little over 400 lumens for the 15 and 18 watt Sunbrite ones.
I have tested the nominally 11, 13, 15 and 18 watt Fieldbreeze versions. The 11 and 13 watt ones had a spectrum mostly like that of "warm white" fluorescents with a significant trace of the spectral features of the usual compact fluorescents that have a "triphosphor" phosphor formulation. I believe the color rendering index is somewhat better than the 53 of "warm white" fluorescents. The 18 watt one that I purchased in late 2003 and a 15 watt one that I purhcased in late December 2004 had a strictly "warm white" spectrum. The Sunbrite units have a nearly enough strictly "warm white" spectrum with an extremely faint trace of red/reddish spectral lines apparently from an ingredient typical of triphosphor phosphor formulations.
The color of all warm white Fieldbreeze and Sunbrite units tested was purplish-whitish compared to the usual warm color compact fluorescents and to incandescents. The Sunbrite ones and the 11 and 13 watt Fieldbreeze ones I have found to be a slight improvement in purplishness/pinkishness over the 15 and 18 watt Filedbreeze ones tested before, but still so purplish-pinkish that I have had difficulty estimating correlated color temperature. I am currently estimating the correlated color temperature of all Sunbrite and Fieldbreeze units tested so far to be 2900-3000 Kelvin. I have in the past estimated some Fieldbreeze units to be "cooler" (higher correlated color temperature) than 3000 K.
Based on the spectrum, I would estimate the color rendering index of the Sunbrite and the 15 and 18 watt Fieldbreeze units to be close to the 53 of regular "warm white" fluorescents. However, skin tones are not as badly yellow-greenish as under "old-tech" "warm white", so I am revising my estimate of color rendering index upward to about 60. The 11 and 13 watt Fieldbreeze units should achieve a little more still with their more significant triphosphor spectral content. Nearly all non-dollar-store compact fluorescent lamps have a color rendering index of 82.
BUG REPORTS: A "15 watt" Fieldbreeze was dead on arrival, and an "18 watt" Fieldbreeze had its base get hotter than usual. An "18 watt" "Fieldbreeze" that I sent to The LEDMuseum "Punishment Zone" reportedly after about 1 year blew out with three loud (but unequally loud) "pop" sounds and output of lots of foul-smelling smoke. All Fieldbreeze units that I tested claim "incandescent replacement" wattages that I consider unrealistic - with the "18 watt" being the worst in claiming to replace an "85 watt" incandescent while being dimmer than most 40 watt incandescents.
Capitol Electric 11 watt warm color models
Capitol Electric 11 watt compact fluorescents have frosted glass outer
bulbs. One version has a tubular outer bulb and another version has an
outer bulb shaped like a regular or "A-type" lightbulb.
Both versions claimed to produce 550 lumens of light, but actual light output
according to my tests was approx. 375-400 lumens when fully warmed up. The
light output was slightly higher, in the 400-450 lumen range, when these
were most of the way but not completely warmed up.
The color is like that of most non-dollar-store compact fluorescents,
except they become a whiter, more "halogen-like" color when they warm up.
When fully warmed up, the color temperature is approx. 3200-3300 Kelvin.
The bulb-shaped version may not "overheat" quite as much as the tubular
version does.
The spectrum is like that of most non-dollar-store compact fluorescents, although the red and green phosphor bands weaken during warmup. The color rendering index is presumably somewhat less than the 82 that most non-dollar-store compact fluorescent lamps have, but may be as high as 82 before these are fully warmed up.
Both versions have a model number of 2011W, a UL symbol and elsewhere on the base "LISTED 6G59", and "FCCIDNQXPL". Most other dollar store compact fluorescents lack an FCC ID and any sign of UL listing. 120 VAC compact fluorescents marketed in the USA require an FCC ID if they have integral electronic ballasts.
Spiral Dollar Store Models UPDATE 4/19/2008
In late July 2005 I purchased for $1.49 at a dollar store a "SUN Lighting" spiral. The package claims a wattage of 36 watts and makes no claim of light output. My estimate of actual power consumption based on heat output is 12-15 watts.
I estimate light output to be 400-425 lumens, slightly less than that of a 40 watt "standard" incandescent.
The package says "SOFT WARM WHITE", but the color is actually the icy cold "Daylight" bluish white that is usual for dollar store compact fluorescents.
UPDATE 12/24/2005: A "Tyrone Imports" spiral rated 36 watts and claiming to produce light of a 150 watt incandescent performs similarly to the above "SUN Lighting" spiral model.
UPDATE 5/28/2006 Hongyao 36 watt spiral appears similar to the above two. Light output of the Tyrone and the Hongyao appears to me to be about 450 lumens, about that of a 40 watt "soft white" rated to produce 445 lumens.
UPDATE 12/12/2006: Tested - a "30 watt" "Sun Lighting" spiral. Performance was like that of the above "36 watt" "Sun Lighting" unit.
UPDATE 2/14/2006: TESTED - Two "Sun Lighting" / "My Products"-"Sun Lighting" spiral models, one nominally 20 watts and the other nominally 25 watts.
UPDATE 6/5/2006: A nominally 15 watt "Sun Lighting" one was purchased and tested.
UPDATE 5/13/2007: A nominally 13 watt "Sun Lighting" one was purchased and tested.
UPDATE 11/25/2006: A Trisonic nominally 20 watt spiral was puchased and tested. It was similar to the "Sun Lighting" "20 watt" one.
UPDATE 6/23/2007: Trisonic nominally 13 and 15 watt spirals purchased and tested along with another 20 watt one.
All had "cool daylight" color. All claimed to replace incandescents of 65 to 125 watts but were dimmer than 40 watt incandescents. They were anywhere from only slightly dimmer to at least 30% dimmer than 40 watt incandescents according to a color-corrected light meter and my eyes.
All had a spectrum that indicated that the phosphor was "old tech" halophosphate, sometimes with a small trace of triphosphor.
UPDATE 6/29 and 7/6 2009: A larger size nominally 15 watt Trisonic spiral with model number TS-CFL15WB and claiming "Soft White" and "60 watt replacement" was tested. It had a "daylight" bluish white color, and light output in my testing not exceeding that of a 445 lumen "soft white" incandescent.
Most other "dollar store" compact fluorescents I have found to be strictly halophosphate and most "non-dollar-store" compact fluorescents I have found to be strictly triphosphor.
UPDATE 9/12/2006 - "SUN Lighting" 32 watt spiral "Soft Warm White" is actually basically warm white. The color is very noticeably purplish-pinkish. I estimate the correlated color temperature to be roughly 2900 K. The spectrum appeared to be like that of an "old tech warm white", so I guess the color rendering index to be not far from the 53 of "old tech warm white", maybe a little more based on how skin tones appear under this light. Light output was slightly less than that of a 445 lumen 40 watt "soft white" light bulb.
UPDATE 12/6/2006 - "SUN Lighting" 22 watt spiral "Soft Warm White" is smaller, with fairly pinkish warm white color, and similar spectrum and color rendering. Output was slightly less than a 445 lumen 40 watt "soft white" incandescent despite the back of the package having a comparison chart saying that it compares to a 100 watt "normal light bulb".
I have seen some spiral compact fluorescents for $3 at a few dollar stores, not of any of the "usual" "dollar store brands", and apparently better than compact fluorescents of the "usual dollar store brands".
UPDATE 8/20/2007 -Telstar "23 watt" LB-1023 and "26 watt" LB-1026 spirals TESTED. These claim 70 and 75 watt incandescent equivalence respectively. I have found both very slightly dimmer than 40 watt "soft white" incandescents.
These are daylight models, but with a spectrum that is mostly "triphosphor" in character, so they have better color rendering than most other daylight dollar store models. However, their packages claimed "soft warm white light" while the color of the light is an icy very slightly bluish white.
UPDATE 11/5/2007 -Telstar "18 watt" LB-1018, "20 watt" LB-1020 TESTED! Claimed to replace 60 and 65 watt incandescents respectively, but my test results are same story as the above 23 watt one.
UPDATE 4/19/2008: The above 18 and 20 watt Telstar spirals that I purchased have unequal ratios of "daylight" to "triphosphor" phosphor, with the 20 watt one being about or somewhat over half "daylight" and the 18 watt one being mostly roughly 6500K triphosphor.
BUG REPORTS of dollar store spiral models, other than on light output and color:
6/23/2007, a Trisonic nominally 20 watt spiral had a somewhat noticeable "swirling/snaking" effect.
11/5/2007, I bought another nominally 23 watt Telstar a couple days before this date and found the glass tubing attached so loosely as to be wobbly.
Tripletwintube dollar store models - UPDATE 3/30/2008
Two different units of the Trisonic brand purchased in 2005 claimed to produce 1800 lumens of light. One had a nominal wattage of 25 watts and claimed to produce the light of a 125 watt incandescent. The other had a nominal wattage of 30 watts and claimed to produce the light of a 150 watt incandescent.
Both of these, in my testing, produced very slightly less light than a 445
lumen 40 watt "soft white" incandescent.
UPDATE early 8/7/2005 - after 2.5 days resting after several hours breaking in,
light output has improved slightly to about matching that of a 445 lumen "soft
white" 40 watt incandescent.
UPDATE 5:30 PM EDT (9:30 PM GMT) 8/7/2005: A different test indicates light output of about 480 lumens, maybe 500 lumens. This is "medium-high" to "high" of the range of light output of 40 watt 120V "standard" incandescents.
Both came in packages claiming "natural soft white light". They produced light of the usual icy cold bluish "daylight" color.
Bug reports: TEMPORARY - Both flickered and had a "snaking"/"swirling" visible effect of the arc in the tubing. This effect is not an indication of a hazard. These effects stopped after these units got "broken in", and this may require as much as several hours to 2-3 days of off-time after several hours of runtime.
UPDATE 9/10/2006: a nominally 25 watt Trisonic tripletwintube purchased on this date lacks a lumen claim, but is claimed to be equivalent to or to replace a 125 watt incandescent. Its light output was no more than, if anything slightly less than, that of the other "25 watt" Trisonic tripletwintube purchased a little more than a year before.
UPDATE 9/12/2006: the Trisonic purchased 9/10/2006 does not have the "snaking/swirling" effect of the ones purchased a little over a year earlier.
UPDATE 12/17/2006: A nominally 25 watt one of the "The Brightest" brand (if it has a brand at all) is similar to the Trisonic that I purchased on 9/10/2006. It has a claimed light output of 1800 lumens, but in my testing was very slightly dimmer than a 40 watt soft white incandescent rated at 445 lumens.
UPDATE 3/30/2008: Nominally 25 watt and 30 watt "The Brightest" units purchased on this date did no better. Also, the spectrum is like that of an "old tech" "Daylight" fluorescent.
Update 1/27/2008: Telstar "26 watt" tripletwintube - claims "soft warm white light" but has icy cold daylight color. The spectrum is mainly like that of a "daylight" fluorescent with a bit of triphosphor content. Its light output in my testing is slightly less than that of a 40 watt "soft white" incandescent rated to produce 445 lumens, but it claims to be equivalent to much more.
UPDATE 9/12/2006: "Sun Lighting" "30 watt" "soft warm white" tripletwintube actually has a basically warm white color. However, it is the most purplish-pinkish "warm white" of all dollar store warm white compact fluorescents that I ever tested. I guesstimate the correlated color temperature to be around 2900 K, but the color may be so purplish that a correlated color temperature is hardly valid. The spectrum is mostly that of "old tech warm white" but with a significant trace of "warm color triphosphor" content. The triphosphor content has a higher ratio than usual of red/reddish content to green content. Light output was slightly less than that of a 445 lumen 40 watt "soft white" incandescent.
I invite anyone knowing of a "dollar store" compact fluorescent, that is one sold in dollar stores for $2 or less and of a brand or "brand" mainly found in dollar stores, to outshine a 40 watt incandescent rated at least 445 lumens and to do so significantly and repeatably and in different situations, please e-mail me! For that matter, I am not saying how badly dollar store compact fluorescents do with the deck stacked against them, but in the same situations and conditions where I test other compact fluorescents!
(Daylight-color models *may* outperform 40 watt incandescents and in
good cases may do as well as 60 watt incandescents in larger, dimmer areas
by having a spectrum that is favorable to night vision.)
14 models had claims of light output in lumens and all fell short of their
claims, 8 of them obviously by a factor of well above 2. Two models claiming
1800 lumens produced about 500 lumens or at best hardly more than that. A third
model claiming 1800 lumens was even dimmer, with light output around 400-450
lumens according to my testing. One of the models claiming 1800 lumens has
dropped its claim of light output in lumens.
UPDATE 12/17/2006: Most of these lack the FCC ID that 120V AC compact fluorescents with integral electronic ballasts are required to have if marketed in the USA. Most of these also lack the UL listing that 120 volt AC compact fluorescents with integral ballasts normally have.
UPDATE 1/20/2007: A "Teng Fei" model or series of related models is affected by this 2004 safety recall.
11 of 69 models tested had a "warm white" color, but mostly severely more purplish-pinkish than non-dollar-store compact fluorescents of the usual warm/incandescent-like basic general color. 57 of 69 models tested had a bluish white "Daylight" color, sometimes slightly more blue or greenish-blue than the bluish Daylight "standard size" fluorescents. 13 "Daylight" models came at least sometimes in packages claiming "soft warm white light". 11 other "daylight" models came in packages saying "SUN Lighting" and no other apparent mention of the color of the light, although "SUN Lighting" is the apparent "brand" of some of these. Nine others that actually had a "daylight" bluish-white color came in packages saying "natural soft white light".
The actually "warm white" ones were Fieldbreeze and Sunbrite models, "Sun Lighting" "22 watt" and "32 watt" spirals, a "Sun Lighting" "30 watt" tripletwintube, and two Capitol Electric models with different shape outer bulbs and the same model number.
Actual power consumption is generally 7-13 watts, although these different models have nominal wattage anywhere from 9 to 36 watts, mostly 11 to 25 watts.
Of approx. 80 units tested, 15 had problems:
One had an unusually warm base. (This was an "18 watt" "Fieldbreeze".)
Two were dead on arrival. (One was a "15 watt" "Fieldbreeze". The other was a
"20 watt" "Sparkling".)
One flickered and had especially low light output even in this class. (This was
a "13 watt" "Lumilar".)
One burned out after just a few minutes of use, and in the process made
sizzling sounds and smoke and had a "burning" orange glow in its base. (This
was a "13 watt" "Telstar".)
One of a few that I sent to The LEDMuseum "Punishment Zone" reportedly failed after about 1 year of use, and with three loud (but unequally loud) "pop" sounds and plenty of foul-smelling smoke. (This was an "18 watt" Fieldbreeze.)
One that I used for only a few hours was sent to the above "Punishment Zone" for spectrum analysis, and it flickered wildly on first use after arrival there, and on the next start after that blew out with high output of smoke and a significant "burned popcorn" odor. That one was a "25 watt" Hongyao.
One had unusual inability when cold to start until I touched the glass tubing (or waited two minutes if the room was warm but the bulb was cold from being in a cold location). This one was a "20 watt" one of the "Tyrone" brand.
One developed an intermittent internal connection. It was a "20 watt" "Sparkling" HW-2303.
One had a loose internal part and rattled when shaken. However, it did not electrically malfunction. This was a "20 watt" one of the "Cixing" brand.
Two Trisonic tripletwintubes purchased in 2005 (but not one purchased in 2006) sometimes had a very visible snaking/swirling effect. This effect occurs mainly during first use after a very long period of non-use.
One Trisonic 20 watt spiral also sometimes had this snaking/swirling effect.
One came apart so easily that it was coming apart while still in the package. If it has a brand, then its "brand" is "The Brightest", although the packaging has what I consider significant resemblance specifically to "Trisonic" packaging.
One had the glass tubing being so loosely attached as to be wobbly. This was a Telstar "23 watt" spiral.
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