RE: Alternative Motors
Grimracer himself recommended this one:
[link]http://www.offshoreelectrics.com/proddetail.php?prod=dh-gpmg5290[/link]
I use one, it's great. The stock ESC handled it fine, as long as you don't put too large of a prop on it. (Use the stock prop, or the Grimracer 40/52 3 blade prop).
[link]http://www.offshoreelectrics.com/proddetail.php?prod=dh-aqub9720[/link]
I use that one on the Ammo 2300 motor all with the stock ESC (on 6 cell packs only) and it works fine.