I started with the Volt, then got an eGo-type battery (I'm not even sure what brand...it's black...and I think 1000mAh...yeah I'm kind of a ditz) and some Boge cartos and some clearomizers (which I generally love, except I keep smashing the little O-rings on the tips into the threads when I screw them down). I think the cartos that came with the Volt batteries are fine, but I like the Boge ones a little more. I want to keep using the Volt batteries when I go out and about. I just thought it would be nice to be able to use the same cartos on both the eGo and Volt batteries.