It seems that many of these different brands of e-cigs are actually the same basic unit, often with universal specs and universal connections. I looked at the website for Eversmoke, and read the info about the different
batteries, but didnt see any real specs listed about capacity, or connectivity, aside from their "claims" that you will get 250-350 puffs off them. Thats lame!
If you could contact them and ask about the voltage and battery capacity of both units, and if they are both the same battery chemistry( like Li Ion), and the threads are the same between the 2 chargers, then you should be OK. For instance, I have standard size Li Ion batteries at home for flashlights, and I know that if I buy different brands of Li Ion chargers, they should all charge my Li Ion batteries just fine. I do stay away from crappy chargers and crappy Li Ion batteries though.
BY the way, do you really get 250-350 "puffs" off them?