If you're going to run the stock chevron tires, I've found you need 180inoz to turn efficiently - more than that is overkill that runs your rx batts down that much quicker. I went with lighter tires and rims as well - SportMax wheels and Sporttrax tires losing over almost 2 oz per wheel if I remember the numbers correctly. That alone made a big diff in the way it handled and accelerated.

I've had good service from the Ballistic rx pacs they make for Tmaxxes - I have an old 1650 that lasts for complete weekend of running. I think they are up around 2500 or 2700mah now. This is made into the stock batt box and replaces the stock one. Get a new switch with a separate charge lead and all you will have to do is just plug it in, no more taking the batt box apart to re-charge batts. The rx is not worried about power - its volts. As long as you don't change the voltage, mah won't matter - mah is more about how long it lasts.