;DI purchased the Tamron 24-70mm f2.8 VC on 5/4/12 for $12889.00. Unlike my Tamron 17-50mm f2.8 VC, this lens has very good noise and CA control. The focus IQ is much improved and the VC is truly impressive. It is sharper and has less distortion than any Canon 24-70mm f2.8 (series one) that I have tried to date. It is also sharper than my Canon 24-105mm f4 and my Canon 17-55mm f2.8. On a full-frame, this lens by Canon standard is not a true 70mm. It is more like 66-67mm. However, it compensates by being brighter at f2.8. This lens seems to be at it's best from f2.8 to f7.1. It gets just a little bit softer at f8. I am very happy with the performance of this lens. Into my camera bag it goes with my Canon 70-200mm f2.8L IS II and 70-300mm f2.8L IS.
Hey! same blurb you posted on BH's site review on the lens; you must really like it!
Well, your glowing review prompted me to have a closer look at it.
I checked the MTF charts for the Tamron 24-70, both Canon 24-70 L and compared to the Nikon equivalent.
The new Tammy certainly seems to be sharper than all of them wide open altho the new Canon 24-70 L II is close in some areas.
Another edge the Tam may have, judging from the published MTFs, is slightly smoother bokeh.
I'm certainly going to watch for actual test results on this one, I think it may make a suitable complement to the D800e I'll be waiting for .. interminably.