I love the 7 cell packs. They will give you a ton more power. My stock emaxx will flip over on its top in 2nd gear with the 7 cell 3000mah NIMH packs. The Superbrain is a great charger for these packs and the are around $45. If you get 2 of the Superbrains, you will be able to charge both packs at the same time. Of course, if it is for your son, the 7 cells may be a little too much. When you compare the prices at around $25 for the 6 cell pack and $29 for the 7 cell, for your son I would go with the 6 cell packs for now. Then when he gets a good handle on driving the emaxx, get a couple 7 cell packs.


Hope this helps,

-Austin
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