I am concerned about the esc getting hot, my friend runs 21.6 volts to his 2 700s and the motors are ok I have 3 700s, I just tested it set on slow impluse, not supposed to be as effecent but does not whine, I will try it tomarow set on high impluse and if it heats everything up I will go to 10 cells, If I knew about this problem in advance I would have gone with 2 pro boat $40 ESC, 1 for 1 motor and 1 for 2 motors hooked into one control with 2 Y harnesses with 12 volts. I allready run2 700s with 1 proboat on 12 volts on a trojan. I have been running the PT ON 14.4 VOLTS.