wv2win, they lasted around 10 hours of regular usage and the quality of the hit was exactly the same as the Tenergy's.
EDIT: They didn't completely die in the end, the vapor quality diminished greatly. I'm thinking they don't have a circuit that turns them off after they hit 3v because they're non rechargable. My Tenergy's work dandy, and then, completely off, but that is cause they have a circuit that turns them off once they dip below 3v, so they don't reach the point of no return.