differential spool & battery ????

[redshift]

The Tenergy Nimhs had a very poor reputation, but the Tenergy lipos seem to be quite good, only caveat is the 2S packs are 4 cell/paralleled which is not ideal, they have more of a chance to go out of balance. Friend of mine has two of the 25C 2S 5200 packs and they are very punchy.. I have two 2200 3S 25C packs and they are also very good.

As for the spool, the biggest problem I have had, if one wheel becomes locked (rock jammed into wheel) then there is no relief, and you risk mangling driveshafts.