I sort of have a couple cheap ones from home depot in the 65 watt equivalent wattage ,,, seen to last forever. I know they're over 2 yrs old on a photo cell. Actually bought the R40 style indoor bulb.. replacing par38' cf's , hey they're under a eve.

Look inside the bulb its the standard twisted cf fluorescent in a glass wrapper with some silver paint for the reflector. My temps don't drop often below freezing but those bulbs always seem to start and work fine. That outer envelope keeps the heat enough to let the twisty bulb wall temp reach full brilliancy when it is cold and windy out.

Work just fine for me.

Try a couple. The biggest I've seen were 23 watt. I lit my backyard with them for a while but got tired of the 2-3 minute warm-up time and switched the fixtures out to one's that take a 26 watt pl type tube. The fixtures including the bulb ran about $40. If your's are dusk-to-dawn warm up is not a problem.

Thanks for the comments. I think I will try the Sylvania CF's.