Looking at the photozone 15-85 and 17-85 tests on the 50D, I can't help but feel like the differences have been a bit overhyped. Judging from posts on this forum, the 17-85 is worse than the 18-55 kit lens and the 15-85 is practically L grade. However judging from these reviews, the 17-85 really doesn't seem much worse at all. It only loses on the wide end at the extreme corners, and at the telephoto end it actually beats the 15-85. Distortion is slightly better for the 15-85 at the wide end, but still not admirable, but vignetting is worse. CA is about the only category where the 15-85 really pulls ahead, but is still not great at wide angle.
Am I missing something here? Is the 15-85 overhyped, or is the 17-85 really not as bad as people like to say?