I have the Sigma 17-70 excited for half a year and am of the image quality. The focal length range of 17-70 is in many situations (eg Expedia) yet sufficient, so I do not have to use my telephoto lens. The situation is different, however, from when processing. After around 600 trips the transmission of the autofocus was broken and I had to return the lens. After 4 weeks I got the lens back finally. Since then, it squeaks, however, when I go forth the tube! But since I do not even want to do without four weeks on the lens should I arrange myself so that I would have only a telephoto available otherwise.
