I buy brand name batteries (Everready or Duracell), generally, or at least supposedly, more reliable. I gave up on Steripen a few years ago--couldn't get it to work even with the directions along and my electrical engineer son helping, My summer headlamp (Petzl e+lite) and my bathroom scale also use the CR123 batteries. I'd rather pay more and risk less than get the cheaper generic or house brand batteries.

IMHO, your water treatment system should have a backup when taken into the wilds. Katadyn or Aqua Mira chlorine dioxide tablets weigh next to nothing, certainly a lot less than the extra fuel and fuss required to boil water if your electronic gizmo or filter give out. I've had both happen!