Other than a DOA stick I got a couple years ago, any Mushkin DDR2 RAM I ever got is still running just fine. A pair at a time, that's probably not much more than a dozen sticks, but I'd say that's a pretty good record.
Edit: But yes, Mushkin has a reputation for producing quality RAM, although their prices can be a little high.
Mushkin usally gets good reviews and I have seen them used on OC'd systems, check out Newegg.com to see what others think about the brand/model your looking at if you havent already. And just to help give you peace of mind they offer a Lifetime Limited Warranty.
Yeah, what about a lifetime warranty, does that seriously mean I can return it anytime..
I not 100% sure about this as I have not read into it in detail, but most companies will replace the RAM as long as you have it and is determined to be factory defective and not damaged by any type of missuse. I dont know if they will replace RAM that was damaged by OC past the factory specs. I would assume no. It must be defective though you cannot just return it on a whim. Also I belive most other brands of RAM offer the same thing.