This Zeiss 50mm f/2 Makro-Planar is much better made mechanically than most SLR lenses today. Optically, this Zeiss lens is no better than Nikon and Canon's new and used 50mm, 55mm and 60mm macro lenses, which sell for only a fraction of the price. All of these macro lenses are excellent, so don't expect the Zeiss optics to be any better than the plastic autofocus lenses from Nikon and Canon; they aren't.
The real benefit of this Zeiss 50mm is if you need close-focusing and fast f/2 speed, which neither Nikon nor Canon can match. If you just need a super-sharp 50mm, 55mm or 60mm lens for general and casual macro use, Nikon and Canon's lenses offer the same optical quality, and often autofocus, for a lot less money.
This Zeiss lens is manual-focus only. It will not autofocus on any camera.