So i was looking at getting a standard zoom lens to replace the kit 17-55. I have a 70-200 f/4L, so i figured i would get a 24-70 f/2.8, and later get the 10-22 canon. Basically, ive heard a lot of talk about the tamron option(28-75 f/2.8), but my cousin whos a professional photographer(shoots for a newspaper in SD) says tamron quality is nothign close to canon, but the sigma(24-70 f/2.8 macro) is much better build and uses better glass than the tamron. So what do i get? I'm leaning towards the Sigma now what do you think?