I have this lens, and its performance is acceptable. You can get some unpleasant distortion at the 12mm end, especially when shooting wide open in certain lighting conditions; it's less noticeable in some situations than others. It feels plasticky, especially compared to the classic solid Nikon lenses that gave you things like "real" focus rings, but it's not the cheapest-feeling lens that Nikon makes and I'm not afraid it'll break or anything.
I would recommend this lens if the Tokina 11-16mm f/2.8 didn't exist. It's a little cheaper, a little wider and faster, and will give you images of the same or better sharpness. This lens is not bad, but it doesn't exist in a vacuum. I'd only recommend it if it's cheaper than getting the Tokina.