I've been using my new Soligor 135mm f2.0 quite a bit recently and have been pleasantly surprised by the results.
When researching the lens before actually nabbing one, I saw many complaints of flare problems. The lens has a pale straw coloured coating that does not look like it would be too effective, but I have not had any flare problems to date. I did fit a a metal tele hood to the lens as the built-in lens hood is only 16mm deep, I suspect that the built-in hood is the cause of other folk's flare problems as it is really not effective and probably lulls them into a false sense of security.
Above "stereokeh" pic taken with Sony a7rII, f2, 800 ISO.
I have a thing for fast 135mm's and one oddity with the Soligor was its cleanliness, there was zero dust or debris inside the lens. Every other "vintage" 135mm I've got had to be stripped right down for cleaning; the Sigmatel, in particular, had a huge lump of stuff between the elements, and I never did find where it came from, or how something that big got in there in the first place.
The 1970's seem to have been the boom decade for fast 135mm's and sure enough, the Soligor hails from 1974. It is much sharper and more contrasty than the Soligor 135mm f1.8, the Sigmatel f1.8 and the Spiratone Plura-Coat f1.8, and is about on par with the Rokunar (Spiratone) f1.8, the Canon FD f2 beats all these. Or at least, that's what I found comparing the copies of these lenses that I have/had.
I think that this one is defintely a keeper!