I used to run the Protek one until my second one sh8t the bed....I now use a 3S 15c 2200mAh pack for my heli and it works just fine. Honestly gel cells are rated at 12V and a fully charge 3S lipo is 12.6V so it's got plenty of juice. A 4S lipo comes in at 14.4V so you're actually overpowering your starter box motor. It's no big deal, but overtime the motor won't last as long..... my 2 cents