I had to RMA my 4870x2 last month. New one is working great, so far. If something happens to it for any reason, I am gonna hold out till the new cards have been out for at least 6 months... just incase I can get a 5 series upgrade. But I honestly hope it runs good for a long time, I love this card, the finest graphical experience I have bought for myself. In total honesty, I want to be blown away by next GPU purchase. I have bought two cards in the last 4 months, and before that I was getting a new graphics/computer setup every 2-3 years. It used to feel awesome to upgrade to a drastically new piece of technology, and while the transfer from 4870 512 to 4870x2 was great for gaming, it didn't totally rock my world like previous upgrade experiences.
Maybe a 6890x2 will be my next goal, provided this card can survive a couple generations (and XFX doesn't lose the ability to repair/replace it).