I was fortunate enough to find a tremendous deal on one of these used, and would agree with most of the review except for the big deal made of this lens not having a USM motor. The throw on the focusing ring for a lens this wide is pretty short. USM on a longer lens is a much bigger deal. The build quality of this baby is great. It balances well.
Optical quality is great.
Joel Alves from Rio de Janeiro, Brasil. Image quality like very good prime lens. Amazing color saturation and contrast. Very litle distortion. Very sturdy construction.