Hmm, curious. Is that exchange policy good for ANYTHING, not just repairs? That seems like an odd policy, if they would accept a return next year, for example, if HD-DVDs are no longer made. If that is the policy, then I don't blame you at all for taking the plunge. After all, the picture and sound quality is still really good--and I know that the possibilities for extras are great (even though discs that take advantage of that are few and far between).
I have a couple standard Superbit DVDs, which are basically DVDs with no extras but with high bit rates (Lawrence of Arabia, Panic Room, Bram Stoker's Dracula are a few that I have). They look and sound pretty good themselves.