Ran a few packs through it this weekend. I used two Neu 4S 4100 30C packs. A tight fit in the boxes, but they made it. The torque was incredible. What was really surprising was how cool everything stayed. After a full pack the MGM was warm, not hot, to the touch. The MGM also exhibited none of its previous quirks with braking or reverse. It ran smooth and solid. It all just proves to me that higher voltage setups are the way to go.