I'm just trying to find a cheaper alternative. If I can get away with running a 6S 4Ah pack, then that would make me happy. If I could use the truerc packs, that would make me even happier. I have probably a couple thousand dollars worth of lipos laying around and am ready to go on the cheap.

The FP 6S 3700 looks nice, but I wonder what the runtime would be like.

Whatever I go with, I'd like to stay around 500 grams. At just over a pound it would be perfect.