WD's RMA service is excellent, definitely above average. OCZ's is on-par with most other manufacturers IME, not better and not worse. Just the typical you send the part to us on your own dime, wait a week or so while we take our sweet ass time to process it, then we send a replacement out deal.
Anyway, FWIW, I've owned a 60GB Vertex and 120GB Vertex 2 and both worked great. But anecdotal evidence doesn't really mean squat, you need to look at the aggregate data. This article has some interesting info on return rates (which, keep in mind isn't necessarily the same as failure rate, it could include returns that are due to user error, people returning drives that worked fine but they just decided they didn't want, etc.) for HDDs and SSDs with a French computer parts retailer.
http://www.hardware.fr/articles/810-6/taux-pannes-composants.html
One interesting thing is that the return rate is higher for SSD in some cases than HDD. Suggests that SSD may not in fact be more reliable than a well made HDD. It also lists return rate for SSD by brand. Most seem to have a pretty similar return rate, between 2-3%. For example, based on the data I don't think you could claim with a high degree of certainty that Corsair SSDs are more reliable than OCZ. However, I think it's pretty safe to say that Intel SSDs tend to be much more reliable than other manufacturers.