The only thing I didn't like about the v1 f1,2 nokton was the extent to which it intruded into the VF. The distortion, the weight, the build quality, etc. -- all these were not an issue for me in use.
Ted -- I think v2 and v3 lux 50s are very similar in rendering. That said, I have used both and have grown to prefer the 'sweetness' of the OOF rendering of the v2 -- the coatings in the v3 do make a bit of difference which is just subtly different. The ,7m or 1m is the big difference in use. The subtle rendering difference is what makes the v2 a small gem of a lens, albeit with 1m closest focus limitation.