I've never been able to get a definitive answer for this but which would you choose? I would rather have the 65w so I would need fewer bulbs but some say that the larger bulbs are less efficient.
I have the same question and have been pondering my cfl setup for days now. I read in several threads that the efficiency is indeed lessened the larger the wattage. It's called Lumens for Wattage. 26 watt CFLs are the most efficient out of all of the CFL bulbs I believe, that does not include the T-series fluoro's. With that being said - Which ones do we go with? Having a dozen bulbs is messy. I would rather shell out the dough for the 105s at $37 a piece to make it easier to work with. I was thinking about taking two 85s (or two 105s) and putting them side by side in the cab. You may be able to fasten together a good hood too? 6500K - 400 Watt Equal Compact Fluorescents | 1000Bulbs.com Also I just found this thread http://forum.grasscity.com/lighting/838656-efficiency-cfls.html
13w to 32w generally have the best efficiency. No need to do tons of research just divide the lumens by the wattage. The higher number the better. Simple! Note that they vary widely by manufacturer. Also check out the rated hours. The best are around 12,000.