It might look cool. However, the added grip would come at the cost of easily moving your feet around on the pegs. Not only do MX-style footpegs have more aggressive profiles, but they are also much wider (making it easier to ride off the saddle and on your feet). A MX-style peg would definitely be a bigger hunk of metal sticking out there at extreme lean angles, too.
That said, it's a totally reversible experiment. Try it, but keep your receipts...