Guys, with 7.4v in 12th scale the motor would be something far slower to compensate. Steve could figure out roughly just how many winds they really could go with the current wire size, and if possible/needed, something thinner. Can also change rotor magnet length. There are numerous somewhat simple ways to offset the voltage increase. capacity can be had with different configurations. magically orion has 3 batteries nearly identical size but 1600mah in difference. 3200 - 4800. Either they're not using the space or the batteries are some how magically getting better. polymer can be made into literally any shape. Don't be surprised if somebody lays out a chassis with a battery going as far forward as the servo while mounting the receiver and speed control on top of it. Could really shorten those motor wires.
stuff like this should be standard reading for anyone involved in this conversation.
http://en.wikipedia.org/wiki/Lithium_polymer