I have Joe's brakes front and rear. Well, actually the fronts are on my Manitou which is on a shelf right now. Anyway, I love them. Really nice feel and braking modulation when combined with the finned Matthauser pads. I haven't tried other pads on them, but I suspect they work well with just about anything. They are really rigid which probably helps a lot.
I don't know a ton about the history. There are two different canti arm shapes, one for front applications and one for rear. My pal Earl Bob was sponsored by them for a while when he was racing for Fat, which is how I found out about them. I can snap some pictures if you like.