And to contrast the above, I'm two for two with regards to bodies and lenses that worked like they were supposed to. It's half luck, and half preference. I'm fine with a beater - someone else may deem my camera in need of service.
Once again: Medium format cameras are generally built to the same standards as 35mm SLRs, if not better. You can have the same expectation out of a medium format camera as you do for your 35mm cameras.