I ran a castle 2200 with a MMM in my old Losi E buggy and it was crazy fast on a 14T pinion and stayed pretty cool. The hottest the motor ever got was 150-160 after running 17 minutes. But it did cogg and wasn't very smooth. I switched to a Mugen ECO and went with the Tekin 1900. It isn't quite as fast but it is unreal smooth! It is so nice not to have to wait on the motor after a bobble or spin out like I had to do with the castle. Only thing is the Tekin is running a little hotter. After 12 minute main last weekend it was 175-180 which is hotter than I want. I still like the Tekin better though!