I've been vaping with my vamo and love it. Yesterday, I changed my battery and thought I put a charged one in and it was dead. I was running late to a meeting and didn't have time to go back and get a charged batt. Luckily i had my first set up the ego twist bat in my car that i haven't touched since I got my vamo(bout 2 months ago) it was charged 2 months ago and not touched. In desperation i screwed in my evod and worked like a charm all day! Not gonna lie, I was really impressed it still worked and kept its charge. Even happier I didn't have to resort to an analog. It's been 5 months and still going strong! Always have a back up! Keep calm and vape on!!