I'm running a couple of truerc 5S2P 8Ah packs in my Muggy with an 8XL and MM esc. The pack doesn't even break a sweat. I don't know how it would do in a 4S setup with a hotter motor, but in my truck it doesn't seem to be having any problems. He ships very quickly too. I ordered my packs on a Saturday and got them on Monday. The bang for the buck is unquestionable.