I just got my Titan and I am here to tell you, if you dont have one get it NOW. I haved used TW products for a while, been a 901 fan for a while too. This 510 is the cats ...! The manual battery is great and getting two atomizers is awesome, I dont have to wait for my other flavor to burn out now I can just use the other atty. My only complaint is the auto battery is super sensitive but I found that I just unscrew it while I'm in the car or a noisy enviroment. Good job TW, you are truly a great company!