.18 OS CV-RX Overkill for an RS4?

[PoPRC]

Is this too much motor for a HPI RS4 Evo? My buddie blew up his T-15 that came stock with his HPI RS4 3. So he goes to Al's today and somehow manages to walk out with an OS .18 CV-RX. It was a good price(109.99) and apparently the guy behind the counter said thats what people where putting in the RS4s, drops right in. It doesnt drop right in but I got it to fit and mesh right after some careful doctoring. I might get one myself, but I dont want to find that I can't control the car because its too powerful. I also dont want to make my buddie feel like he made a bad descision. But I gotta know before I go get one. Whats the best motor to drop in there, .18 or other size? I here nothing but good things about OS motors.
Thanks.