I've never seen a 18W quad tube CFL. Only in higher wattage.

Run forever these things

@dor123: Got some lower wattage quad tube CFLS paticulary made by Sylvania @Angryhorse: Totally, these will outlast many cheap LED bulbs for sure

These were very common back in the early 2000s. Cheap but pretty much always put in the hours!

I have found the 14W and 18W to be less reliable personally, but the 8W and 11W just won't die, they go on for ages! Especially good considering the cold starting too.

These are my absolute childhood favourite (2nd to the GE Biax ones of course) but they have to be one of the best budget made CFLS as with some exceptions that Beta 5 pointed out, that overall they keep going and going my Aunt used them all over her house when they were the ones to buy back then - I did encounter a lot of 11W and even 8W ones failing as I once helped her to change them - however I think it was some slight overvolting that her house lighting has