Why not shoot with medium format, just in case?
While medium format cameras have a small quality advantage, they have a tremendous practical disadvantage: they’re slow. Really, really slow. A photographer shooting medium format might be able to get off one shot every few seconds. So, during the bouquet toss, he’ll have one shot. Whereas using my Nikon D2Xs, I can fire as many as 24 shots during the same time. The odds of getting that perfect shot are greatly in my favor. Today’s wedding photographer’s job is totally different from the old days, when a typical wedding consisted of just shooting groups of posed people. You were shooting people who were standing still in a controlled environment. Today’s wedding photographers are more like photojournalists, moving rapidly and capturing the events of the day as they unfold. A photographer shooting a medium format camera will miss many opportunities simply because his camera can’t keep up.