"I like the lense. It is a great walk around lense which is light and fast enough for situations where other lenses fail. I used to have the 17-85mm EF-S Canon lense before and was looking for a faster alternative that is having a good wide ancle" bhphotovideo.com
" I got a chance to test multiple samples of this lens with multiple samples of Canon's 24-70L, and this lens outperformed the Canon lens, especially in the center" bhphotovideo.com