Tamron SP 15-30mm f 2.8 Di VC USD

Anyone out there who has one of these and can provide feedback? I'm currently looking for an UWA to go with my EOS 5DS ; the image stabilization and 2.8 f-stop this has makes it seem quite attractive as the 5DS is unforgiving to say the least with regard to hand-held shots. UWA primes with IS seem to be as rare as that brown stuff from rocking horses so a short zoom like this would appear to be the next best option. Online reviews of the Tamron appear to be positive mostly but there are not that many around as yet. I have tried a Canon 16-35 f4L but was singularly unimpressed with the copy I received and subsequently returned. Maybe I should try again?

I love this lens. I use it with my 5DIII and it is super sharp all across the frame. Autofocus is super accurate too and the distortion isn't all that bad either. It controls flare pretty well too for a wide angle. I've never regretted my purchase. I had the Tokina 16-28 and the Tamron is just much better.

Thanks Ku
just the sort of info I need.

Follow-up Jan 22, 2016....I have now bought one and I am very happy with it so far. Knocks spots off the Canon 16-35 f4L IMO even though I got a fair amount of flack here when I gave my less than favourable impressions of that lens. The Tamron is around the same price but is f2.8 and sharp wide open, neither of which applied to the Canon I tried.
2nd Follow-up Jan 22. Have now completed focus analysis of this Tammy using Reikan Focal Pro. Quality of focus (QOF) is between 1800 and 1900 from f2.8 to f11 which is a very good set of results. At f16 the QOF drops to around 1500 and then to 1400 at f22, probably due to diffraction. The same series of tests on the Canon 16-35 f4L could not produce a QOF better than 1520 at any aperture.