Yes it seems just awesome. hopefully Lightrules will have some first hand experience for us soon.
First, sorry folks but no pictures currently. I have two copies and the better (i.e., nice!) one is going to Lloyd up in Canada. The copy I'm keeping is going in to Tokina service. It has a decentered element issue with the left side quite a bit blurrier than the right. This was discovered after I noticed a consistent pattern of this, even without looking at 100% crops.
Apart from this issue, the lens is certainly sharp even at f2.8. The center of the frame is superb. CA control is slightly better than the 12-24 and similar to its 16-50 sibling...just slightly below average. Colors and contrast are superb. Flare performance looks average to above average; I'd rate it better than the Sigma, just a nod below the 10-22.
I can't wait to get this puppy working right. It looks "prime-like" otherwise. Highly recommended...apart from decentering!