I regularly used Nikons loaded with FP3/4 to make fashion prints on 60" x 40" paper. (Well, to be accurate, I farmed them out because I couldn't handle that size in my darkrooms.)
For colour, it was Hasselblad with Ektachrome. The thing is, when you make a vertical like that on the larger camera, you are only using the height of the 120 film to advantage, and it's not really all that much bigger when looked at in that way, but every little helps.
However, it all came down to viewing distance. There's no way I'd claim that a print the same size, from a similarly fine-grain 4 x 5 film would not scream superior quality. It depends on so many factors: movement, flash or available light, contrast... everything and anything can conspire to make the same format work or not work. You just have to know how the print's going to be used and act accordingly.
Don't forget: visible film grain is often acceptable and even a contributory factor to mood; I can't think of an occasion when the digital equivalent of pixels can look cool. I have spent a lot of time wandering hospital corridors, looking at huge, decorative prints meant to soothe people and their nerves; if they are old film photographers, seeing all those horrible pixels up close could be counterproductive.
Rob
