Hello, I am considering stepping up to a better MF camera for studio type work. I have been shooting with a Yashica-D for sometime now and am looking for something a little better. I am looking into something 6x7 and the Mamiyas seem to have a good reputation. My question is, do you guys think I would be satisfied with a RB67 or should I fork over the extra cash for a RZ67? What exactly are the differences? Are there any other cameras I should consider, I was looking also at Pentax 67's. Thanks in advance.