I work with an EOS 400D and have so far been given a lot of good pictures with a Tamron 70-300mm. For the zoom range I was looking for including a suitable lens and I ended up after much research the Sigma 17-70mm. The lens is very well made and has a pleasant feel. However, it is somewhat difficult, but hardly bothers me. It focuses quickly and is quite bright. The image quality is good. Hardly distortion at wide angle range. Images are sharp, colors are very beautiful. Also good performance in the macro range. You can take the lens touching the object and almost the autofocus still works. I have so far been shooting indoors, nature, buildings and portraits and rate the results as well. In a single image in the macro range with spot autofocus I got a back focus. The lens is ideally suited for the price a good allrounder and for the ambitious amateur photographers.