i think you're going to get soft edges with either of the lenses. if i were buying again, i'd get the tokina. theres some VERY cool stuff you can do with it at 2.8. find an 11-16 group on flickr, you will see what i mean. but on a cropped body, i dont feel you can completely eliminate the soft edges. if you really wanted to do so, you'd have to go full frame. just my 2 cents, and yes, i do have the sigma. until i can afford the 24-70, ill shoot my sigma the majority of the time. i am shooting a lowly XTI still though. i'd love to have a 5d someday, but it wouldnt be anytime soon. im sure i'll shoot my XTI until the day it dies. i love camera stuff, but its just a hobby. so i wont be spending big money on gear anytime soon. as crappy as my offbrand lenses are compared to L glass, im perfectly content at the moment. the only thing i wish i had was another flash and some triggers. someday..