One big question to take into consideration is weight. Medium format gear is generally heavy and bulky. If you plan to always shoot close to the road, then fine, go ahead with the Pentax 6x7, it's fantastic, but very bulky. Hasselblad lenses are 2 pounds each...
The other big question in my opinion is camera service. As much as I love Bronica, I find it more an more difficult to get them serviced. The GS-1 is awesome, very efficient, super sharp and somewhat small and light for this format. With a couple of lenses it can fit in your backpack. Pentax cannot, in my opinion.
Also, rangefinders (Bronica, Mamiya) are usually great, but have their limitations.
And finally setting up the larget format means less shooting, sometimes you will miss some shots. On my last visit to California, I had the GS-1 and a lightweight 4x5 set up.