I've had CFLs in most of my fixtures for a long time. Multiple generations of CFL design. It's been a mixed bag of joy/tolerance. Some crappy, some noisy, some with stupendously short lifetimes. Even within a production lot, some last forever, some die in a year or two. One consistant thing: lumen degradation over time. This is sort of like the frog in the cold pot set to boil - it's hard to tell that it's getting dimmer until a significant event.
Most of my ceiling fixtures are recessed cans. I expect a lot of the early CFL failures were thermally induced (crappy caps @ elevated temps). I've been watching LED bulbs progress with the hope of replacing some key CFLs. The tough part is finding ones that:
- aren't insanely expensive or low efficiency (ie: wattage savings over CFL never recovers the purchase cost)
- aren't 2700K (might be nice in a den or bedroom...too frigging yellow for office and kitchen)
- will work in an enclosed can fixture
- have a decent warranty / are a brand that I trust to follow their warranty
- decent CRI (that said, nearly any LED beats out the average CFL)
Until recently, it was "chose 3 of the 5 criteria". "Aren't 2700K" and "work in a can" seem to be mutually exclusive

I bought two for my office to try them out. They replaced a couple of ancient 20W ~1100 lumen spiral CFLs. The combination of moving back to a BR30 reflector and the (now) obvious lumen-decay of the CFLs led to a "Gah! It's bright in here" moment. I like the color rendering - way better than the CFLs they replaced. Plus, instant-on rather than the multi-minute warm up time of the CFLs. No noise, either.

The payback is still out there. I can get 640 lumen 15W BR30 CFLs for $5. I have the lights on in my office for a good 8 hours a day / 7 days a week. So, the 3W improvement in efficiency is about $1/yr for a 13 year payback. That said, my past experience with BR30 CFLs has been less than stellar. I only have 2 left working out of ~12 I installed 3-4 years ago in the higher use areas with the highest death rate happening in year 2. So, if $5 CFLs last 4 years, then the payback drops to 8 years. Whether or not the LEDs will last this long is a future post.
* of course, I'd have to ship the bulb to Ohio with the proof of purchase
