I have the EF-S 10-22mm f/3.5-4.5 and love it! After reading several of Bryan's Sigma lens reviews Ihave becomevery wary of them. It seems like every one he gets his hands on has both focusing issues along with softness on one side of the lens. Also, what does the new Sigma cost? The reason to buy the old Sigma 10-20 over the Canon was a $200 premium for the Canon version but Sigma's latest releases seem to be getting much closer to Canon's prices. From what I hear, Tokina owners can't say enough good things about their ultra wides. I know that the 12-24 f/4 is extremely popular. The 11-16 f/2.8 is fast but as far as zooms go, at 1.5Xit's not that versatile.