Well, I don't know what's your point of having 6x6 or 6x7.. or let me put it this way - how big prints are you going to make? If its up to 5x which is already quite impressive enlargement for hanging it on the wall, then go a head and give a 6x4.5 a try. Surely, there are more (with good price/quality ratio) alternatives in the 6x4.5 world - Mamiya, Pentax to name two.. besides Bronica. I used an old Mamiya M645 w/ 80/1.9 and 55/2.8 and had sold it only because I badly needed to raise funds for my Rolleiflex, otherwise it would have stayed.