I used the Volts as well 78mm batteries and cartos with 12mg juice, I was a PAD ultra light smoker. It worked for me... BUT, I had to vape about 20 minutes worth for a 6 minute cig break equivalent. Absorption of nic is slower with an e-cig. My friend who was also PAD of ultralights needed 18mg and 24mg juice, but vapes less. You can either increase the nic, or give yourself more vaping time per cig. You'll have to experiment because we're all wired a little differently. I'm now using the Volt X2 batteries 650mah is about a cigar size with a clearomizer, and loving the all day battery life... so if you get to the point you're tired of charging... feel free to move up. Smokeless Image has a forum on here as well if you need any help after you've made your first 5 posts.