Kim, can you figure your power to weight ratio of the A123's compared to a Lipo? Most people are only using 75-80% of the LiPo capacity, so the cell weight is kind of deceiving. Also, have you found the advertised discharge curve(nearly dead flat with a very steep drop right at the end) to be true? i.e. after a short intial power burst the motor runs at a steady rpm until just before it suddenly runs down completely?