Hi guys. I have a Pentax 645 and want to go a little bigger-no I'm not interested in LF camera, so please don't suggest that I am interested in the earliest model with MLU. So I guess this would be the second version?? Is this a good choice? Are they reliable? And there are several finders available. Will any finder fit any 6X7/67, or do certain finders only fit certain versions of the camera? I wanna get a non metered prism for the challenge and to give my Sekonic meter some use.