Hello all I've been an amateur and semi-pro for several years of 35 mm and DSLR shooting, but now I have a strange "itch" get my hands on medium format and it has to be SLR of 6x4.5 format. Now, from whatever small research I've done I can see that Bronica ETR system is the cheapest one AND it can be bought piece by piece (which is good, considering my ridiculous salary). This leads me to my question: I know that there are several 6x4.5 Bronica cameras (ETR, ETRC, ETRS, ETRSi) and most probably I will be aiming for the cheapest and oldest ETR, but what bothers me is this - does any ETR 120/220 film back and viewfinder fit any ETR body, or is there a specific film back and viewfinder for different bodies? Also, what are the actual risks/consequences of using 120 film in 220 back (since 120 backs are not so often met online) and is there a way to overcome those? Any advice is much appreciated. P.S. I'm not hellbent on getting Bronica, if there's anything worth mentioning financial- or mechanical-wise, I'm more than willing to rethink my decision. M.