The KGO, as I understand it, is an SLB 1100 batt, so it's really no different from any of the other ego clones. E-Power, on the other hand, uses replaceable
batteries like the 18650 so it's kind of a different ballgame. I've had problems with the power button on the 18650 version but I hear they're fixing that somehow. I like SLBs - 3.7-4v and pretty durable. For a standard ego form factor they're fine, as are most of the other clones.