I switch all of my lights to CFL and all of them are E26 and not GU24. I had to buy a GU24 adapter because the light housing in front of my garage door is GU24. I have no energy comparison, but I do noticed some last less than advertised while others have last for 5 years and going. So, maybe it has to do with the housing itself that cause the early death. I got it over 5 years ago when SDG&E and Home Depot were doing some special deals on them and I got them for ~$1/bulb. I stocked up a lot and still have plenty. I can’t justify going to LED because they’re still way too expensive compare to my $1/bulb CFL.