Steve I understand completely...if I could take photos as good as the camera could produce you would be paying me money for my photos! I am certainly the limiting factor.
In mthe Mamiya RB and 645 line there are no dogs in the lens line up to my knowledge.
Nikon does have some lenses that are....less capable????
I do not know enough about the Bronica line up to know it the 200mm is a good lens or not.
I have a Mamiya M645 1000s and a Bronica ETRS complete kit and there are several things about the Bronica system that I like better than the Mamiya 645 system. If only my metered prism would work on the Bronica!