I felt the hobbywing 4000Kv felt a little soft on power for my tastes. I had to go full throttle and turn my punch control almost off to get the power i needed to make a double right after a hairpin. I was geared @ 16t on a medium sized indoor clay track. Motor had awesome top end, just lacked a lot of the punch i'm used to (tenshock 4600). I'm almost positive the reason my motor felt gutless was due to my season-old nanotec packs. I'll have some smc 6500 race specs as soon as they're back in stock. If anything, i bet that's my problem. I will comment on how efficient it was. Only put 2500mah back into my nano's after a 6 min main.