I don't own this camera so take my comments accordingly:
I never understood this camera. While it is cheaper than a Mamiya 7, if you are going for a MF rangefinder, why not get a 6x7 format camera? It also has a funny orientation that I have never understood--to get a landscape photo you have to hold the camera in its vertical aspect (and visa versa).
With Bronica exiting the medium format SLR business how long will they support this camera.
I own and love the Mamiya 7. I think for the price of a new Bronica 645 (there are not that many used ones since its relatively new), you can get a nice used Mamiya 7. And the Mamiya with the 43 or 50 mm lens is amazing.