Summary: In terms of construction and optical qualities, such as resolution, chromatic aberration, and vignetting, this lens certainly makes worth its high price. This lens is among the finest lenses for cameras with an APS-C sensor. Distortion, especially at the ends of the zoom range, is not (yet?) corrected by the camera.
Pros: Optical top class quality (resolution, chromatic aberration and vignetting), Solid as a rock
Cons: Heavy: almost a kilo, Visible distortion at 24 mm, High purchase price