> I've seen a couple of air-blade installations, and in those they have slowed things down because paper towel dispensers allow you to take a towel, step back, and dry your hands while another person gets a towel.

I largely agree with your points, but I wanted to point out that most modern bathrooms(and certainly not bathrooms that may have this device deployed) don't have paper towel dispensers. So it isn't a question of paper towels vs this technology, but this technology vs the hot air fan, or the dyson air blade, or other similar non-dead-tree tech