I've been thinking about getting a Jupiter-9 to play with. I've read as much as I can about the different versions (silver vs. black, coated vs. MC) but I'm unclear on the mount. Specifically, is it true that a version using the Contax/Kiev RF mount will require an expensive adapter to allow it to focus? I know there are inexpensive Contax RF adapters, but my understanding is that most (all?) of the lenses made for the Contax RF mount used a coupled focusing mechanism in the body and so won't focus without a complicated focusing mount adapter. I'm curious about the Contax/Kiev mount versions because they are cheaper--but obviously won't be if the adapter costs >$100. Can anyone clarify this for me?