That bomb use for the RC's is pretty cool and cheap as hell.
I'm with the rest of the gourp on the batteries, the more the mah, the longer the run time. I did notice a small power gain switching to a set og GP cells on my sons stock Emaxx but you probaly wouldn't see that with aftermarket motors. As for the Dual esc's, I would simply save my money and buy a Brushless system. You'll probaly end up spending that much money on buying dual esc's and better motors to run with them anyhow.
Anyways, nice truck.