I agree with Chris... The mamiya 6 was a great system, and the glass was unparalleled. That said, finding one in good used condition could be a challenge. The Mamiya 6 system can be fragile. The winding mechanism's can and do break, and once that happens, you have a paper weight. There are no spares for the winding mechanism, and other spares are hard if not impossible to find. I sold mine as a result of that, and went back to the hasselblad, after moving away from it initially to buy the Mamiya system. I did love the quality of the negs that the mamiya created, but to be honest for what I use cameras for, the hassleblad was and continues to be the most versatile set up I own. Does your current hasselblad have the accu-matte screen? I upgraded my 500 c/m with one after I first bought it and was the best upgrade to the system. If you have trouble focusing, get one with the grids and split circle. You will not regret it. Also, dioptre correction is possible with the waistlevel, and a good upgrade to the waistelvel finder is the chimney finder. It's focusable to adjust to your eyesight, and does not distort like the standard waistlevel sometimes does.