You can find Rx packs now up in the 2200mAh-2500mAh. Get the right configuration (hump or flat) and you should be good to go. If you are racing, you can get your qualifiers in on one charge, and then top it off for the main. If you are bashing, put it on the charger after a 20-30min run and see what kind of voltage you got left, this way you can see just how long you can run on the battery.