I bought my KR8 starter kit (manual) from My vapor store.com and I love it! I bought 2 more KR8 batteries from My vapor store.com. Just got done charging the 1st one and its like I'm vaping air. Don't know how else to describe it. I thought maybe I had a bad carto, so I put my carto on my orginial KR8, and the carto is just fine. Do I have a bad battery, or do some batteries need a "breaking in" period? I haven't tried my 2nd battery yet, it's still charging.