definetly listen to marty, i only run 1600mah+ NIMH from radicalrc, sirius charger is the best charger i have found, i never use the wall charger anymore, i also prefer 5 cell packs, with a 600 mah pack you probably would spend most of your time quick charging at the field instead of flyn. the sirius charger is somewhat expensive, but thus far it has been well worth the price