If you are going to get a 510, I would difinitely get the manual batteries. Also I like nhaler.com, rockymountainvapor. They are here in the US and they both have good customer service and get your orders pretty quick. I have also heard a few good things about cignot.com. Whoever you decide to buy from, I would suggest just trying it. I smoked for over 23 years and it is the only thing that has ever gotten me to quit for any period of time. Good luck!