Personally, I only buy lamps from either Philips or Osram, and I haven’t bought any of the recents from Philips, because a few of them died prematurely … after just 9 months of light use.
I use the Osram Twist/Mini-Twist 20 or 23W because they’re about 1/3 shorter than the straight twin tube versions, and the 23W is more than a match for the 100W incandescents.
I have various el-cheapies floating around in the cupboards for miscellaneous uses like table lamps, but I refuse to use them for the main lighting because a) they die quicker (and ceiling lights can be a pain in the rump to access), b) The randomly flicker or take a long time to start and c) The colours are all FUBAR compared to a reliable brand.
Unlike incandescent lamps, which come in a single horrible orange colour, Compact Fluorescents come in many different colours - incandescents are supposed to be warm white/3000deg Kelvin, but I personally prefer the Cool White/4000deg K - but since the missus yells the loudest & gets the most complaints from the neighbours, warm white all over the house, and my computer room (aka the spare bedroom) gets Cool White
It’s important to remember that when buying cheap CF lamps that you must be open to any colour light … because el-cheapy lamps are never the colour that’s written on the box, and sometimes you get a muted rainbow of colours, if you get a 6 pack of lamps, and you should buy a lottery ticket if you get two in the box that are a colour match with eachother, let alone what’s written on the box
Daylight = 6500degK = Same as the sun (apparently) … you won’t fall asleep with the lights on, but you probably will get eyestrain, and be cranky/irritable.
Cool White = 4000degK = Home Work Colour.
Warm White = 3000degK = Home Colour.
Interna = 2700degK = Sleepy Colour.
Damnit, I’m looking at buying a house soon, and everything I’m looking at is either 50yrs old with ancient architectural lights which would never fit a CF, or fitted out with f@#$%n halogen downlights (which is the stupid trend in Oz). Halogens are slightly more efficient than incandescents and are next in line to be banned … and at only 25lm/w, about 2/5 as efficient as a [reputable brand] CF