Is the leica tri elmar m 16 18 21mm f 4 asph worth it?

Here is what the site says about that.

From Leica Tri-Elmar-M 16-18-21mm f/4 ASPH: Leica Tri-Elmar-M 16-18-21mm f/4 ASPH: A zoom lens by Leica for Full frame cameras, 16-21mm f/4. Three ultra-wide focal lengths in one lens. Specs - Maker: Leica - Focal length: 16-21mm (zoom) - Maximum aperture: f/4 - 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, 16-21mm. Cameras it fits - Leica M9: Full frame ...

From Sensor sizes: Is full frame worth it?: For low light, events, and portraits with very shallow depth of field, yes. For travel, street, wildlife on a budget, and most hobby photography, a good APS-C camera with good lenses is enough, and you'll carry it more. Lenses and light matter more than the last stop of sensor performance.

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