the blu pcc is kind of annoying because you have to screw it in and screw it off once its done. It only has one light which is solid while the battery is charging and blinks when its done. but you have to take it off as soon as its done charging or it drains your blu battery and your pcc battery. I really like the way the 510 pcc works, other than i cant fit a complete ecig inside like the blu. which i dont understand, seems like an easy thing to do. just make it a tad wider and add an extra slot. but whatever im extremely happy with my 510 and my 510 pcc. UPDATE FROM SUPPLIER. got an email this morning and he contacted his factory representative and it is a smart pcc, so it will stop charging once the battery has recieved a full charge. I got mine in an ultimate combo pack which i thought was a pretty good deal. 2 batts, 2 attys, 5 carts, wall charger, car charger, pcc, a passthrough, and a 30ml bottle of juice in your selection of nic and flavor for 85 and got free shipping. bestecigshop.com