Geez....FWIW, 600 ma. pack on non-digital servos is no problem ....generally, servos draw little current if not in action. I have been flying 4 flights without charging with 500ma. packs for more than 20 years with never a battery failure. That beign said, 1000ma. packs are so cheap today, it's a no-brainer...lol...don't fly if the loaded voltage falls below 4.8volts...big_G