Depends on how screwed up the back is.
I get overlapping frames sometimes but it has been awhile considering I don't use those backs unless I'm trying to figure if I want to attempt to fix it.
Here is the repair tutorial
http://www.mflenses.com/koni-omega-back-repair.html
I think one issue is your ratcheting action/advance action.
If you are not deliberate and use the full stroke you can get overlapping.
All the lenses for this system are superb and the 58/60 is reported to be one of the best.
It's non retro focus so the design can deliver less distortion and better sharpness into the corners if that is something you need.
Neither of the teles will really focus all that close so if you are into tighter headshots you may be out of luck.