Gentlemen,

Your 1000, 1300, or 1500mah batteries will go much farther than you think on your ignition. The RcExl ignition draws the 450ma at 9000 RPM. Our max is well below that and who flies at WOT all the time. I've run a DL50 on a test stand with a 1400mah NiCad for over 4 hrs continuos, no stops. It would have kept going but it ran out of fuel. RcExl ignitions will also run well at well under 4.8 volts.