run the mg66!...but if you dont have enough $ then get the gx-7r!...what are you running it in?....alot of people have been running the gx5r cause it has the best of both worlds on the top and bottom!..but it also depends on what tracks you usually run on!..either choice you will love em!...i cant wait to get me a mg66!...maybe we can get the MASSIVE MODS name more common out here in RCMECCA SOUTHERN CALIFORNIA!