Thanks. I didn't know enough re self-discharge for the Nitecore 3400 mAh battery, so I ordered a charger which comes with a 3400 and also a couple 2600 batteries. If the discharge on the 3400 is on par with the 2600 then I'll order a few more of the 3400 capacity batteries. I've got a few lights besides the SF which can use 18650 batteries.

Remember when a Surefire incandescent was considered bright?