Hi Piece,
It is probably difficult to give you a general answer without knowing what you intend to do with this camera, now and in the future.
- if you intend to transform your film camera into a digital platform at some point of time, then the Hassy H series is probably a top contender, with what are probably the sharper lenses out there, even if many seem to prefer the look of the Contax lenses.
Other options are the Mamiya 645AFII, the older Hassys (but there are no interesting square digital backs...), and... the Contax 645... officially dead, but still rumoured for a revival.
- If film is your only thing, then format might be a good angle from which to look at things. Do you want to shoot square, 6/7 or 4/3? For square, Hassy and Bronica (dead though) are the most obvious options, along with some more exotic Russian stuff. Hassy lenses are way more expensive than everything else, but appear to be in their own league,
For 6/7, look at the Mamiya RB/RZ and Pentaz 6/7 (no changeable back though),
For 4/3, then the Hassy H, Mamiya 645, Contax 645, Pentax 645... are the obvious options.
- What kind of shooting are you in? For commercial shooting, a changeable back is probably a must, which means Hassys, Mamiyas, Contax, Bronica,...
If landscape is your thing, then weight and robustness are probably more important. The Contax 645, Pentax 645/67II, Mamiya 7II are good candidates. I have been using my Hassy H1 for landscape too, but it is rather heavy.
If street shooting is of interest for you, then the rangefinder like Fujifilm bodies, Mamiya 6 or 7II and Bronica are very good options.
Regards,
Bernard