@Drevly: Yes, more power means more heat and more juice. I was going through 2-3 ml a day with my eGo and normal attys. That went up to 4-5 a day with 3.7v + LR or 5v with standard attys.
@Brad: That sounds about right, but my knowledge of electronic theory is only at a novice level. I learned it many years ago and most of it has trickled out of my brain.