I have a light which looks identical to this. I got it from wallbuys for $8 (if I recall correctly) during a sale.
http://wallbuys.com/Product/UltraFire-CREE-LED-XML-T6-1000-Lumens-18650-Battery-FlashlightBlack-6016
It’s the best zoomie I’ve ever used, aside from being a tad bit large to keep with me. It has a wider flood than any other zoomie I’ve seen (75 to 80 degrees, the lens is almost touching the LED dome), the zoom is almost as narrow (7 degrees?) as my narrowest zoomie (wider-lens variation of the Sipik SK-68), and it’s quite bright on high. The entire flood area is twice as wide as the SK-68 and yet still brighter, so it must be putting out as least 5X as many lumens. I’d estimate around 700 to 900 lumens on the wide setting. However, when zoomed, most of the light dies on the inner aluminum wall without reaching the lens, so it doesn’t throw anywhere near as far as a dedicated 1xXM-L reflector thrower.
Overall, it’s one of my favorite lights… and it obsoleted every other zoomie I have. The only things I don’t like are its lack of useful mode memory (always cycles to the next mode, regardless of how long it was off), its blue-tinted LED (seems like a 0A/0B/0C/0D ~7500K tint), and its overall size.
With an 18650 battery, my unit is quite a bit brighter than 3xAAA. I haven’t been able to actually measure it, but visually it seems to be roughly 3X as bright (2X to 4X, really). It should last at least an hour on high, probably at least 2 hours on medium, and at least 6 hours on low (but possibly as much as 20 hours, depending on the power used, probably more like 8-10).
I haven’t had any heat issues with it, but the body does heat up fairly quickly on high so I assume the heat transfer is working. However, as with most zoomies, the heat goes mostly into the part of the body which is covered by the zoom piece, so it kind of insulates itself unless it’s on the narrow setting.
Now, if I could figure out what this item is actually called, I’d put it on the list in my sig below.
Edit (2+ years later): The Jax Z1 is my current favorite zoomie, after modding it with a dedomed XP-G2 and FET driver. It gets the same nice wide beam but can throw around 200 kcd, and it’s built far far better than the cheap light I posted about above.