I have two CV adapters, 28/90 and 50/75; and an old Leitz adapter for 35/135. I have encountered no problems when using these with CV 28, 35, & 75mm lenses; and with my 50mm LTM Summicron. Really there are not supposed to be any problems. I have no reason to anticipate problems with FSU lenses either, but not owning any, I can't say for sure about those. As long as the thread pitch is correct on them, they should not be a problem either. But recently a problem was reported that sounded like it might have been due to thread pitch on an FSU camera. So I suppose it's not out of the question that this problem could occur with some (certainly not all) FSU lenses as well. I can't recall reading any complaints about the FSU lenses so far, though.
Main thing is just to be sure that the lens is seated all the way into the adapter, and the adapter is rotated all the way clockwise until it clicks. It doesn't matter if you first put the adapter on the lens, and then mount to the camera; or if the adapter is already in the camera and the lens is screwed down.
I have not tried the cheap Chinese adapters. Those who have, seem to think they are OK.
“There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey.”