JR DS8711 is what I use and its a BEAST!
403oz torque and 0.15 speed
0.15 is pretty fast and that torque is awesome!
You dont want TOO fast but you need all the torque you can afford!
Found mine on here in awesome shape used for around $75 shipped!
Chris Keen: Viola, Kansas
FT T4.2,T5M, B5M FL*4sale*, Kyosho RZ6, TLR 22 3.0
"I'm too drunk to taste this chicken!", Col. Sanders