I can vouch for the Interstate All Battery Center. On my way to an appointment today I stopped by the Interstate All Battery Center in Conroe, Texas, and picked up a couple of those 2200mAh 18650
batteries and a spare cheap dual 18650 charger for a grand total of just under $20.
The 18650s they sell are slightly wider than the Panasonic 2900mAh batteries I get from
fasttech, and have a button top, but they squeeze into my Sentinal clone mech just fine and fire it right up. While they will not replace my daily Panasonic batteries, or Nitecore charger, Interstate All Battery Center will certainly do in an emergency or when speed is more important than quality. If you bust a charger you could do a lot worse than spending $4 for a cheap charger with them, at least until a good charger gets delivered to you.
That said, not ALL Interstate Battery stores/dealers will carry all batteries. Only the Interstate
All Battery Centers.