are you running a 2s lipo ? if so the output voltage of this lipo pack is over 7 volts and can damage your servos if there not suited to higher voltage. you should run a voltage step down unit for safety or go for a LiFe 2s pack as these are lower in max voltage. 1300 mah is ok but i would keep an eye on the voltage remaining after a couple of runs, yes 2200 plus would be better. Hobby King have some good Zippy receiver LiFe Packs around the 2400 mah size quite cheap.