I have the 35mm ZF.2 (f/2). I don't have an analog camera that it fits, but it is a wonderful lens. Probably the sharpest I have ever shot with.
That said, in anything but a landscape setting, I miss focus with it too often. Modern cameras, perhaps, should have modern conveniences.
If it says Zeiss it's sometimes a Cosina
The lenses are very good but not that much better if any than good Nikon or good Canon optics. I rarely agree with Ken Rockwell but in this case he is right. Ken seems to like the Biogon in M mount. For Slr get a Contax rig and use Zeiss lower priced Zeiss lenses.