i have been able to get over an hour of time from my 730mah pack using 2 digital servos on more than one ocassion
during a race day i charge before qualifiers and again before mains but twice when practicing i have gotten over an hour from the pack using the timer on the radio to calculate
i use a hangar 9 double vision is a DC charger that can charge you radio reciever pack and glow plug ignitor all at the same time