I have a Brison 2.4 & a MVVS 1.6 I always use an 1100 - 4.8 volt pack and can easily fly 7 flights in 1 day no problem. I find my 4.8 battery packs will drop to 4.8 after only 1 or 2 flights but will only drop to 4.7 after 5 more. Neither ignition give me any problems at 4.7 volts.