24-70 f/2.8L II LensRental test

"This is short, sweet, and simple. The resolution absolutely, positively kicks butt and takes names. It is way better than the lens it replaces. It’s better at 70mm than the best Canon zoom I know of, the 70-200 f/2.8 IS II. It’s even better at 24mm than the sharpest 24mm prime we have, the Canon 24 TS-E. In the center, in the corners, it doesn’t care. We only had 5 copies to test, but they were all very similar with little copy-to-copy variation."

http://www.lensrentals.com/blog/2012/09/canon-24-70-f2-8-ii-resolution-tests#more-9233