Is the leica elmarit m 21mm f 2 8 asph worth buying used?

Here is what the site says about that.

From Leica Elmarit-M 21mm f/2.8 ASPH: Leica Elmarit-M 21mm f/2.8 ASPH: A prime lens by Leica for Full frame cameras, 21mm f/2.8. Specs - Maker: Leica - Focal length: 21mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 21mm. Cameras it fits - Leica M9: Full frame - Leica M9-P: Full frame - [Leica ...

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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