Is the sigma 20 200mm f 3 5 6 3 dg contemporary worth buying used?

Here is what the site says about that.

From Sigma 20-200mm f/3.5-6.3 DG Contemporary: Sigma 20-200mm f/3.5-6.3 DG Contemporary: A zoom lens by Sigma for Full frame cameras, 20-200mm f/3.5-6.3. A 10x full-frame travel zoom that starts at 20mm. Specs - Maker: Sigma - Focal length: 20-200mm (zoom) - Maximum aperture: f/3.5-6.3 (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 marked, ...

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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