You are going to like this: Image quality
results from the Canon EOS 5Ds R
have been added to the Sigma 85mm f/1.4 DG HSM Art Lens Review
I'm guessing that you are impressed with what you see, but the Sigma 85mm f/1.4 Art Lens vs. Canon EF 85mm f/1.2L II Lens comparison
should fully convince you.
Results from the Canon EOS-1Ds Mark III
and Canon EOS 7D Mark II
are coming and will make many additional comparisons possible. But, this lens is certainly looking impressive from an image quality perspective!
Make the Sigma 85mm f/1.4 DG HSM Art Lens your Christmas present! B&H
has this lens
in stock (Nikon) and "coming soon" (Canon mount available for preorder). Adorama
only has the Sigma mount lens in stock, but at this moment is offering a free Sigma Dock