I just used mine last weekend to fix a nightclub's patio heater at night in the dark for 2 hours. Disassembled, changed the thermocouple, cleaned out pilot light line, cleaned out burner, Adjusted flame levels, & reassembled... all with the AAA P in my mouth. Usually it's on my keychain, but removed it to put in my mouth.
It was a hero with the recent Buffalo October storm that plunged 400,000 people in darkness due to downed power lines. A week later some were still without power. It helped me run power inverters, & generators to sump pumps, & furnace electrics in dark damp basements. It was my most used light personally... but I get 7 hours of pretty bright light using a 900 Mah NiMh Tennergy cell, with an 8th hour of much dimmer but usable light.
My most popular (impressed the people the most) light though was my 3-D cell MagLite with a 6 watt focusable Luxeon in it.
My most used, by the people, lights were my cheap, Shorlite AA & AAA LED lights. I have a half dozen of each so just tossed them around. Dimmable, they'll run over 70 hours on the lowest setting... just what you need if you're gonna go a whole week without electricity.
The most useful for just hanging around in the dark waiting for the power to come on were my gear-guide 4-AAA dimmable lanterns. They were originally 12 LED lanterns, but converted all 3 lanterns to a single 1 watt luxeon LED. We also liked our incredibly cheap, 6 3-D cell, 20 LED desklamps made by Innovage. They were under $10 each at Boscovs & Rite-Aid. When i bought them, the last one I bought, I had to repair, new, right out of the box... but it was easy. They have the advantage of running continuous for days on the 10-LED setting with just 3-D cells.
We also had a MagLite 2-AA, & 2 AAA laying around with Luxeons in 'em. But they didn't get used a lot. I think they'll only last a night continuous on a single battery change.
But the ARC P, is the one I personally used the most.
I do a lot of camping, so I was busy upgrading lights to LEDs, or buying LED lights since about 2 years ago.
I'm very popular during power failures & camping trips:
1-ARC P AAA
1-Aitech 6 LED
1-3-D Cell MagLite 6 Watt Luxeon
1-2-AA MagLite 1 Watt Luxeon
1-2-AAA MagLight 1 Watt Luxeon
6-single AA 2-LED Shorelite
6-single AAA 1-LED Shorelite
6-3-D cell Innovage 20 LED Desklamps
3-Gear Guide Lanterns 1 Watt luxeon (modified)
3-Streamlight Stylus 3 AAAA LED penlights. (Bright, 60 hour run time)
1-6-D cell twin tube Colman Fluorescent lantern
1-4-AA Fluorescent with Nite-Ize LED front mod
1-4-AA Fluorescent
1-4-D cell Innovage 12 LED lantern (POS but runs long)
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