Is the pentax hd fa 77mm f 1 8 limited worth buying used?

Here is what the site says about that.

From Pentax HD FA 77mm f/1.8 Limited: Pentax HD FA 77mm f/1.8 Limited: A prime lens by Pentax for Full frame cameras, 77mm f/1.8. Same optics as the earlier smc FA 77mm Limited. Specs - Maker: Pentax - Focal length: 77mm (prime) - Maximum aperture: f/1.8 - Made for: Full frame sensors - Mounts: Pentax K - Stabilised: no - Autofocus: yes What it frames like - On full frame (Pentax K): as marked, 77mm. - On APS-C (Pentax K): like 116mm on ...

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.

Quoted from this site's pages.