[nutz4sand]

Cost. If you can find one cheap it might get a tad more response and a bit more power (the amount depends on several factors concerning your motors condition and any mods it may or may not have done.)

You can spend a lot of money for a tiny power increse. Its your wallet. Jsut be careful to not ruin any reliability it has now. A bit more power is no fun if it cause the machine to break down much.