I get excellent sharpness at all ranges at f/4 and above.
Still incredibly very good at f/2.8.
Color rendition is great, too.
For Nikon mount it uses in-body AF motor so it's great for high-end bodies, and pretty silent to me; but won't focus on low-end bodies. Distortion is very good but I've seen better. Zoom and focus rings are very smooth and give a very high-quality feel. Great price for the features. I can use on full-frame at 14mm (without filters). Build quality is very solid like a tank.
Bokeh is nice, too; I can focus pretty close to the subject, giving it a nice wide area bokeh.
I consider this as a prime lens (only 1.45× zoom).
It has no stabilizer but I don't really care.
It doesn't have weather sealing.