I got my ePower three days ago, and have been using it non-stop since it came in. Batteries were already charged and ready to go. I also bought some dual coil clear mega XL cartomizers from MadVapes at the same time. The ePower is fantastic (in my opinion). I vaped it from 10 AM until midnight, and was still going strong when I went to bed. Next morning it was still putting out the power. Came to an abrupt end about 11 AM the next day. No noticeable drop in power right up to the end. Now as for the XL cartomizers. They do hold a lot of liquid and do produce a good amount of vapor, but I find them to be weak on flavor. I kind of want to compare them to the original eGo tanks. They are also too large for the cone to fit over, even the large cone that comes with the ePower. The rubber tips are extremely tight and a standard drip tip will not fit. However, I was able to vape on one fill for about 6 hours before the vapor slowed down. Going back to my favorite, Boge LR cartomizers really brought back the flavor and the cone fits very nicely, giving the ePower a sleek appearance. I am very happy overall with the ePower, but will continue with Boge LRs until something better comes along. I have not tried the regular sized dual coils yet, but will with my next order. Until then, it will be ePower and Boge LR.