I've used mine 4 times now and love the cordless "life" more with every use. I'm not using mine for hard correcting (I have a 3401 for that) Mine is used for AIO applications. I can get 3/4 of a car from a battery. I could get a whole car with a battery if I hustle faster but I tend to "massage" more.
As for the battery on the end. I think of it as a knob when doing a roof and hold it with one hand and let it do it's thing.