So far, my experience with them (for the price) has been meh. I have only messed with single drives, however... but if I was going to RAID em up, I would probably do multiple 7.2k SATA anyway... for the cost and how much you are actually going to use the throughput.
The biggest problem I have heard of is with heavy writes... but apparently this is only really a problem with first-gen SSDs... with wear-leveling and other enhancements, it's been greatly mitigated.
If I was going to make the switch to SSDs, I would probably go with Crucial's RealSSD... but that is by no means based on exhaustive research.