Good All-around, Convenient Lens
I have to agree with the other 2 reviewers on this lens.
The 883-306 model is for Nikon DX DSLRs. It's a new lens from Sigma. I purchased it a few months ago. So far I'm satisfied. Very compact & lightweight, and a good value. Build and operation is very good. Seems to auto-focus at the speed of my Nikon lenses. As for sharpness, it's on par with my other zooms. I have noticed softness in the upper left corner at 250mm, but it's probably acceptable given the purpose & price category of this model. Chromatic aberration appears quite low on raw images, and distortion is good enough. A pouch or case is not included. Check the review at ephotozine, where they give it 4/5 also. Recommended.