The rating of batteries in mAh can be misleading. 2000 mAh means 2000 mA's or 2A's for one hour. Or 4 A's for 1/2 hour. But you can only take that math so far until the internal resistance stops you. Think of each cell as being a piece of wire, the smaller it is, the less current can go thru it, that's what they mean by high internal resistance. So with the larger subC, you can go down to 20A's or so and the current will still flow thru to the motor instead of heating up the cells. The reason, I finally decided, hehe, for the big advancements in AA tech, is our beloved digital cameras which need big capacity AA's. Stay tuned for more high performance tho, who knows where it'll end.