Bumping this because of a new CR1 on the subject of the rumored Sigma 24-70 f/2.8 OS Art. Alas, the info is thin. While I remain on the fence about the utility of any 24-70 vs prime lens counterparts in the same range for my shooting style, I'm still interested in this.
Having previously owned the 18-35 and currently owning the 50 Art, AF has been terrific, not to mention their other qualities. The 18-35 took a little more effort to fine tune on a 7d, but the 50 Art was nearly perfect right out of the box on my 5d3.
http://www.canonrumors.com …-art-next-from-sigma-cr1/
