My only 135mm is an M42 Russian Jupiter 37A 3.5/135mm which I find very sharp wide open and it produces nice colors. I've had two 3.5/135mm Super-Taks but they were ordinary (not good, not bad) in comparison to 37A.
I don't know how to describe it but all my Russian lenses (Helios 44, Jupiter 37A, 3M-5A 8/500mm mirror) have sort of vintage look to their color rendering which I find very nice and it makes even the not-so-good images (which I have a lot of
) a bit more interesting.