There's a few places over here offer it and some people swear by it. They reckon tyres run a lot cooler so wear less quickly and maintain a known level of grip. As N2 is supposedly dry the amount of damp in tyres which is known to be a killer over time, is vastly reduced. The comment about pressure stability is true so you should be able to set your pressures by trial and error to suit your handling preferences and they should stay where you put them.
Only real downside seems to be that, if you do get a flat, when the tyre is inflated after repair with air as a stopgap measure, and as Brock correctly pointed out, the tyre must be properly evacuated and dried before it is refilled with N2.
Good luck and for one, I'd be very interested in a report posting if you go ahead with it.