Originally posted by andrewd 
If you want to spend a bit more, maybe consider a brand new Voigtlander 40mm lens. These have a beautiful retro design and the optics should be top notch. I don’t have one so no direct experience.
I have the original 40mm SL versions for both m42 and Nikon F. They are very nice indeed both optically and to my taste style wise. The SLII version I have in PKA is also very nice optically and I see no difference between it and the older version, but I do not like the aesthetics of the lens compared to the original. It looks like a very well made lens from Cosina (which is what it is) you would have bought in the late 70's to early 90's. The latest iteration returns to older styling, but I still don't think it looks as pretty as the original. There does not seem to be a whole lot of difference in price between the two older models (used) and a new version three.
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