I would recommend the e-roll without hesitation! I use them since 2 weeks and am completely satisfied. 0.4ml Liquid (max. Capacity) are sufficient for about 30 minutes so steam should always have a bottle of Liquid to refill it. One battery charge of the e-cigarette is keeping about 15minutes. The case I have to recharge every 2-3 days. In order to make comparisons: I have previously smoked about half a pack of cigarettes a day.