I have a 240GB OCZ Vertex III working as a dedicated disk cache for Ae.
If you're putting one in a Mac, you need to make sure to get hold of Trim Enabler. Mac only allows it's own brand of hard-drives to have Trim enabled. Trim enabler changes that for you without you having to get your paws mucky in Terminal.
I've read the reviews and heard that people have had problems, but from personal experience so far so good. I've only had the thing installed for three months though, so who knows. The drives have a three year warranty, so I guess the manufacturers are relatively confident in their sticking power. When I've returned failed mechanical drives I've always found the service prompt and without question, so I hope the same applies here. The estimates that I've heard from pundits with no vested interest are 7-10 years under a fairly steady load. For me, that's fine. I have lots of hard drives that are that age and still working, but none that I use anymore. Simply because the march of technology makes them obsolete after about 5...whether obsolete connectors, too small or too slow or too cheaply replaceable with something better.
I haven't taken the plunge and made a system SSD yet. I'll probably give the first one another 6 months first. I'm going to put one in my laptop though and see how that fares.
I like to look at it this way. If the thing saves a day of work in its life, then it has easily paid for itself.
But don't stop backing up in triplicate just yet.