Yea he can run lipo. He's already running a XXX-4 with a GTB 4.5 and Orion lipo's already. With that setup he usually runs with 1/8 gas buggies anyway.

As for budget, thats not too big of an issue. That OS motor he wants is 300 bucks, so I would say 300-500 dollars would be reasonable. Maybe a little bit more. He is power hungry like me, so what would be the ultimate setup for him.