Is the sigma 20 60mm f 2 8 4 dg contemporary worth buying used?

Here is what the site says about that.

From Sigma 20-60mm f/2.8-4 DG Contemporary: Sigma 20-60mm f/2.8-4 DG Contemporary: A zoom lens by Sigma for Full frame cameras, 20-60mm f/2.8-4. A standard zoom that starts at a true ultra-wide 20mm. Specs - Maker: Sigma - Focal length: 20-60mm (zoom) - Maximum aperture: f/2.8-4 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E, L-Mount): as ...

From Buying used: Buying used: Cameras and lenses are built to last, and many photographers upgrade often. That makes the used market one of the best ways to afford good gear. A body that's one or two generations old is often most of the camera for a fraction of the price.

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