I've had a chance to do some shooting with my Canon 10d, and the Tokina\n19-35mm lens that I purchased with it. I've also been using Canon glass: a\n28-80mm, and a 70-300mm. Frankly, in terms of contrast and resolution, I\ncan see very little difference between the three. There is some slight\nchromatic aberration with the Tokina, which is most noticeable at it's\nwidest focal length. However, it is not very much worse than what I would\nexpect to see with any extreme wide angle lens, short of paying at least an\norder of magnitude more. Is there better glass? Sure! Is the Tokina good\nenough for most casual photographers (not snap-shooters, but photographers,\nalbeit casual ones)? Sure! Oddly enough, my financial circumstances have\nchanged such that I could, if I wanted, buy a much more expensive wide angle\nlens, and I considered, for a short while, returning the Tokina and getting\nCanon glass. However, after looking at the results the Tokina produced, I\nreally can't think of a compelling reason to do so.