Yeah, the weight will certianly be a problem. And the c rating. The cylinder cells don't come with tabs, and so soldering them would be diffficult. Pre soldered oner are over $100 a pack. Unfortunately, as far as my knowledge goes, hobbyking is the only place that cell life po4 packs in higher capacity and cells. Maybe the 4s 4200 would do, I would then only need half of it's c rating, but again weight comes into play. Oh well, atleast I have some time to think this over.

Hubert