I have pretty fair sized Bronica system consisting of 2 SQ-A and 1 SQ-Ai bodies, 3 - 80mm PS, 1 50mm PS, 1 150mm PS, 8 120 backs, a 135N back, a Polaroid back, 3 WLF's, a metered prism, an AE prism, 2 speed grips, an S-18, and an S-36 extension tube, plus a few more odds and ends. I can't say enough good things about these cameras, they're that wonderful to use. The lenses are damn nice, the electronic shutters are super accurate - the whole package gives me a warm fuzzy feeling everytime I shoot with it.
There is one drawback though, when using the metered finders you will find battery life is shorter than you may like. I keep a few spare batteries in my bag at all times.
I learned the battery issue the hard way early on. An SQ-A body stopped synching flash - at a wedding - because of battery level. The battery check light indicated all was well, but nothing short of a new battery would get the camera to work right. It wasn't a big deal as I had a backup body ready to go, but it took a few minutes that I could have better used to choke down dinner to figure out the problem.
One helpful tip I can offer: the SQ-Ai uses four 76 cells whereas the SQ-A uses a PX-28. I only buy alkaline PX-28 batteries and dissect them for the four 76 cells needed for the SQ-Ai - it's a LOT cheaper than buying four 76 cells and it's less for my aging brain to have to remember to buy. A PX-28 comes apart real easy with a pocket knife or small screwdriver.
In spite of the battery issue, I love my Bronica gear!