I dont think it is all that simple. I have been shooting film since the 60's, and have been of the mind that bigger is always better. A few years ago I had something of an epiphany, when I came into both a pentax 67 and 645 at the same time. I did a series of tests, shooting the same subject at the same time and place, same film, processing, and then printed as big as i could go on my omega d2. I was dumfounded to find that the 645 images were sharper, and no difference was to be seen with tonality. So there are lots of other factors that have to be considered- lens quality, film quality, the ability of the body to hold the film truly flat, all those sorts of things. Film size may not always be the limiting factor in image quality. When I bought a contax g2 I was really pissed that the negs were no better than what I was able to get with my zorki; then I realized the film I was using was the limiting factor, and when I changed film and processing, I was abe to take advantage of the really superb lenses to g2 has. Its not as simple as assuming a smaller negative will not be as good as a bigger one.