As promised, image quality results from the Canon EOS-1Ds Mark III have been added to the Sigma 24-70mm f/2.8 DG OS HSM Art Lens page.
We recently shared the test results for this lens mounted to a Canon EOS 5Ds R, but some older 24-70mm lenses have not been tested on this camera. Thus, the 1Ds Mark III results fill in some blanks:
Sigma vs. Canon version I
Sigma vs. Sigma non-OS
Sigma vs. Tamron VC
The Sigma 24-70mm f/2.8 DG OS HSM Art Lens is in stock at Amazon and WEX and available for preorder at B&H and Adorama.