I’m starting my quest for the perfect e-cig configuration by trying to use cartomizers on my SD MKII. I ordered an adapter, 901 to 510 ( Thread Adaptors ) and some cartomizers ( LitecigUSA ). The issues I'm trying to overcome are convenience factor in the car for my way to long commute, consistency of vapor/TH, and to hopefully resolve my flooding issues. Though I haven’t tried many battery setups I feel the SD MKII is as good as it gets in the 3.7v arena. The battery life for me seems to be about 9 to 10 hours of near constant vaping and it seems to me that the performance doesn’t fall off at all. It’s as solid of a hit on the fresh battery as it is 9 hours later, right up to the time it dies so I see no need to invest more money then is necessary until I find fault with my current battery or something far more impressive comes along.