Fans are not evil at all and they wont hurt anything at all they draw their power from the battery. Also this was not an absolute necessity for me I just feel alot better about running at 150 versus 185 (I demagnatized a nemesis 7xl at 200deg) If your running so hot that a fan failing half way through a run destroyes your motor...you have set up issues. A fan is just for keeping temps low and extending the life of your motor or control. I doubt their's a single soul on these forums that would rather run at 190 versus 160. The air blowing from this fan blows directly at the heat sink and blows under it and over it right at the side of my esc lowering its temps another 5-10 deg I swear!