I currently am running my rewired stryfe on 4 1.5v lithium AA's (Energizer Advanced, great batteries compared to even some li-pos) with 2 extras in a power stock. I have Hyper Dash 2's in it and they run like magic. Hyper Dash 2's will outperform RM2's all day, and if you want even more RPM on the same voltage you could go up to Hyper Dash 3's on Tamiya.