yuo could also try eXpress motor sports (txmpress.net) they have outstanding motors and batts. their monsters have so much rip.
for a stock brush/spring combo i say f's on both sides and purple springs. i rollout 3mm less
than someone else w/ same car (brand new monster, i saw him buy it), and he cant catch me on strait
(ps i dont polish my bushings, but it would help)