If you get to a point where you are trying to decide between the trakpower packs and the orion packs, beware.

Although the orion packs are made up of kokam cells, they are not the same cells that kokam uses in their 4800mAh packs. The orion packs are actually 2S2P packs rated for a 15C constant discharge. The kokam packs are 2S1P (or whatever configuration you get) packs rated for 20C constant discharge. The trakpower pack, IIRC, are 2S1P packs with a 20C constant discharge rating. I'd go with the trakpower packs.