Image quality results from the EOS 5Ds R and 1Ds III along with flare, distortion and vignetting test results, MTF measurements and specs/measurements are now available on the Tokina 24-70mm f/2.8 AT-X Pro FX Lens page.
If you have used Tokina's other zoom lenses featuring the push/pull AF/MF switching mechanism, this lens will feel familiar in your hands.
B&H has the Tokina 24-70mm f/2.8 AT-X Pro FX Lens in Nikon mount in stock with the Canon mount available for order.