I've pretty much decided to go with the SS Vamo V2 and an AGA rba of some sort, as a heavy vaper would 2 18350s equate usage wise to an 18650? Not for use stacked but, to shorten the device. One dies exchange with the other... I already have a light saber on my utility belt and would hate to accidentally grab my APV in the heat of battle whilst thwarting some supper villain!