I have this No. 7 Stealth ecig and am wondering if I can use any 510 battery to replace the one that comes with the starter kit. I was thinking about ordering the ego-t battery and using the usb charger that comes with the No. 7 starter kit to charge it. Please let me know if this is posible... or what battery you would suggest, I have about 23.00 left on my card and want to get a long lasting battery and maybe more if possible. I was looking at liberty flights and they have the egot battery for 17.99 plus shipping. Thanks!