I’m a fan of long runtimes, my one mode (moonlight) EDC is powered by a 12V 92Ah lead acid battery that i wear around my waist thanks to makeshift ductape suspenders, gives me great runtime but somewhat affects my buoyancy, i leave footprints in the pavement and am knee deep in any soil that isn’t soundly compacted.
18650 by far, sick of AA and those horrible AAA’s.
I use single cell 18650 lights mostly now, one CH10 headlamp and one C8 style are my go to lamps. Still have a few AA lights around though, just not interested in buying anymore in AA format.
I’ve been told that, in the event of an emergency, and I’m talking city/county/state-level emergency here, the National Guard will be handing out AA batteries like candy, so that’s what I tend to favor. I have a soft spot for tiny little AAA lights and 10180 keychain lights, but I generally get AA if I’m going to spend money.
I still tend to use my J18 the most frequently of all my lights, and I still probably empty 26650s more frequently than 18650s, but I guess I’d have to choose 18650 since I cant fit my J18 in my pocket.
AAs and AAAs are for remote controls, clocks, monitoring devices and Wii, etc.
Mostly I carry a 502B with a 18650 laptop pull. When weather is extremely hot or I need to carry something smaller then It’s a single AA Eneloop in a small inexpensive zoomy.
Currently I have one on my key chain that uses a BLF Tiny12 driver with two stacked 7135 chips. It draws a constant 0.7 A into an XP-E.
I have others that draw 1.5 to 2 amps., but not regulated or controlled. I also carry a Pakistani two blade pocket knife. They both need renewing now and then, but I have time and like to do it.
16340. My EDC gets many short uses during the day so runtime is not an issue, while pocketability is, I carry the smallest possible 16340 light (but with dedomed N219b@2A for a bit of throw).
I’m always wearing skinny fit jeans so pocketability is a bit issue for me, 18650 is a no no. For this reason I carry 602C with triple 219A with Qlite 10 x 7135s. For around house I found SF-348 with 219A to be the best because for up to 3 meters use all I need is 30ish lumens high CRI single mode light.