I NEVER have had my Barnack "borked" becuase I would never hand it to anyone that I dont trust to be a manual camera freak like most of us here are. (hows that for grammar )
It's just inviting trouble, even from a so called repair guy at a shop THESE days which probably means dslr training at most.
Luckily for you, if you feel the camera speeds were out when you received it from Yuri, he will take care of you.
You just need to be honest and talk to him about it.
I dont have a fsu screwmount but I do have a Kiev/Contax and I learned the hard way.
I will continue to gamble with the lenses but the bodies are too much of a crap shoot for my tastes and I LIKE buying old camera stuff. It just needs to have been built right originally. An iffy proposition with FSU. I eventually went with a IIIf R/D.
Now I think the shutter speed dial sequence has the potential of borking you if done incorrectly, but... I think I've read conflicting reports if it means automatic borking or it can accumulate to an ultimate bork eventually.
I would shoot a roll at least and see how it exposes and make a decision from there.