I own both and would never go back to the XL2. Something about the XL2's look is extremely telling that that was the camera used, which is an aesthetic you may want to go for. For me, the H1 is far more versatile, and if I have to shoot SD, I pick up the H1.
As far as comparing the two, the H1 is absolutely worth the extra dough for many reasons, least of all the image. No contest.