DPR and Lensrental have both uploaded some test results of this lens.
Lens looks very good to be honest.
Some interesting findings, but I think in the overall scheme of things probably not super important if making a decision on whether the Tamron is the lens to go with or not ...
DPR's finding indicate that field flatness is better controlled on the Tamron vs the Nikon(obviously at more shallow DOF aperture values.
OTOH, if you look at Lensrental's MTF chart fort the two, it would seem that (theoretically) the Nikon would be the better lens in this respect.
The comments(and images) made on DPR about the Tamron's stated focal length at the wide end are a little disappointing .. in that the lens appears to be more of a 16mm focal length than 15mm.
Would have been nice to be as wide as possible, which of course you can always zoom in a bit if that's too wide for 'ya.
For me, this actually wouldn't be an issue tho .. I have the Sigma 12-24mm for going wide.
Going on these test results .. I'd say as do DPR .. this is certainly one of those lenses with a very high consideration rating.
And so, even tho I already have a super UWA lens(the Siggy) .. this one is definitely a lens I'll have soon enough too.
The VC is one of those must have features(which of course neither Nikon, nor Canon have in their equivalent lenses) for when it comes in handy in specific situations.