A quick priming mouth puff, followed by a slow/gentle 4+ second mouth drag, then a slow inhale. Keeping it in for longer really helps it do its work. I never kept smoke in for nearly as long. In my experience, vaping is just a different beast than smoking.
I was very happy to be rid of the auto batteries. I converted their atomizers/carts for dripping with my ego batteries, so it's not like the money I spent on them was totally wasted.