I should mention something about 26650
batteries, yes, their Mah ratings aren't all that impressive compared to some 18650 batteries these days (which sacrifice ability to hold higher voltage under load in the quest for more mah), but that doesn't tell the story. The 26650 batteries hold higher voltage/amperage under load. Those 3400+ mah 18650 batteries don't hold voltage under load nearly as well especially when you get down into the really low ohm
coils. Sure at 1.5ohms, you don't see much difference, but on my load tester, when I crank up the amperage, those 26650's bury the 18650's.