I have many egos also, some are twists some are not, all were bought from multiple vendors, what I have learned is that these batteries are knocked off by the boat-load every one I have has something sightly different than the others and some of them charge differently than others. And all Whatever MAHs are not created equal. Measuring battery life by the Milliliters vaped is also not a good indicator, there are too many variables. You]ll know when an Ego has gone bad or is not charging properly, micro chip has failed or is shorted out usually by the green light coming on very quickly,or not at all, and if you think its charged get a hit or two off it and then it blinks 7-10 times and wont hit again. I like the egos and I'm going to try and figure out a way to find away to buy original Joytech egos, at least I'll know some of them went through their quality control department.