from what i have seen around, nml are the fastest and the best out of any motor, for heaps of info on that head over to these forums here and goto the motor section, its where nml himself actually talks and answers any questions :
http://minizrac.nexcess.net/forums
as for the ball diff i have a gpm diff with the 1/16″ balls and oh boy is it nice and smooth over the stock 😛
link:
http://www.minizworld.com/modules.php?name=Store&func=ShowProduct&product=18
