I use a Mamiya C330 and a Bronica SQA.
I think the square format suits the subject. The cameras, cranky and old fashioned, suit the subject too.
There is nothing, IMHO, that beats a big negative.
On the minus side, they are slow and clumsy if you are in a hurry; and most standard lenses will provide a max aperture of only f2.8, so that means a fast film when you are trying to stop a speeding train in the gloom.
On the other hand they are robust and simple. I was in Mongolia chasing industrial steam. It was -32 degrees and my fingers were frozen. I dropped the Mamiya on a rock and broke the spool winder. I fixed it, in the field, with a few elastic bands and some duct tape and carried on shooting.
As everyone gets into digital. I may trade up to a 5x7 plate when I can.
A few examples here:
http://www.fotocommunity.de/pc/pc/mypics/712026