I only had issues with it when I got my first one, as it wouldn't co-operate with my Q6600. A few BIOS-releases later and it was all good. And now it's as stable as any. And I even got an extra for free when I RMA'ed the first one cause of a faulty S/PDIF-connector, and that's why the missus got her own computer.
As for the OS, I've been waiting for an excuse to install Vista, and now, seeing that I've won a fast new disk with the perfect amount of space, I could install it without having to delete a lot of (not so useful) data.