savage flux all the way. it will take more abuse, the driveline is more solid, the motor mount is better IMO, HPI has a better warranty, there are more chassis related upgrades, it is just all-around better.
They say a good mechanic only needs 2 tools - WD40 & Duct tape. If it moves, and its not supposed to, duct tape. If it doesn't move, and its supposed to, WD40.