Quote Originally Posted by John Koehrer View Post

Mamiya RB?RZ are the bulkiest, the GS1 probably the smallest.
The Pentax in my opinion is a non contender. It's pretty awkward(for me) to handle.
John, I have a good buddy who owns a Pentax 6x7 camera and takes beautiful photographs with it. I have never shot it but I have held the camera in my hands a few times. I also find it pretty awkward (for me) to handle. I used to own a Mamiya RZ67 camera and my buddy hated it for the same reason.

As I'm sure you well know, it's good to handle and preferably shoot cameras before purchasing.