According to my county you can just throw CFLs right in the trash. The amount of mercury in them is so small that it basically isn't worth worrying about. I don't live in California however, so your trash service may have different rules.

Of the CFLs I installed over the years I've had mixed results. Some are 15 years old and still going strong. Others I have had to replace more than once, although usually with LEDs now. The LEDs have mixed results too, with them being far more susceptible to heat failure in enclosed fixtures. Annoyingly they're usually built around a number of LED elements wired in series, so if any one element goes bad the whole bulb goes dim or fails entirely.

I know people used to complain a lot about CFLs being flickery and having bad color balance, but I only ever had one pair of bulbs (from a two pack) that were really bad in that regard. The pack I bought from WalMart for reasons that are lost to time. They were truly atrocious, one was orangey and the other more blue, and if you looked out the side of your eye you could see the flicker. They also died within a year thankfully, even though both were in well ventilated fixtures. My final point is that I've had much worse luck with CFLs mounted upside down (with the base pointing up). Except for the Wal*Mart specials and one enclosed outdoor fixture I think all of the ones I have installed right side up are still working.