Avoid the 3600 cells from Sanyo. They don't put out as much voltage as the GP3300 cells. Most packs made from GP3300 cells will charge up close to 3900mah.
From what I have seen of the brushless system, it is a bit slower than a good 12 turn motor. Loads of torque however which in a truck works out great.
If I was sticking with the brushless system, I would go and get battery packs in the 1.17+ voltage range matched at 30amps.
Promatch has some great packs if you are looking for a matcher to buy from.
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