My Mercury Extreme Pro 120GB SSD worked perfectly for about 9 months. For the last 2-3 months, it gets corrupted, and I have to restore from a backup. Works fine for a few weeks, then gets corrupted again. Today is the 3rd time that's happened, and I'm giving up now: I'm returning to RAID-0 with regular hard drives. I don't expect to see a big speed hit, as I was surprised that the SSD wasn't a big speed improvement over RAID-0 when I first installed it.
In contrast, the SSD on my Macbook Air (11" C2D) and my previous model Macbook Air has been rock solid. Though in fairness, my Air is really just my travel computer, so it doesn't get used nearly as much as my Mac Pro.
Edit: RAID is rebuilt, the Mac Pro is running fine now. Seems like the Mercury Extreme Pro was faulty. I'm tempted to try an Intel SSD or a Momentus XT but I think reliable hard drives are more important than taking chances on another SSD failure.