If you want decent brake pads I've always used Kool-Stop, they don't eat the rim like the standard Shimano ones do, and seem to last quite a while as well.

As far as bar-spins, adding a brake would be more of an issue if he had a 650 front rather than a 700, in which case he would be using the 650 to "correct toe-overlap" and the easy bar-spin ability would simply be an "added bonus".