If you've been looking for a relatively bright, ultralight, indestructible headlamp, this one is pretty sweet. I'm currently sitting in the laundromat, with my fully functional headlamp sitting to my right. A minute ago, I found this in the dryer.
What the E-light is and is not:
Jess and I both carried Elights for our section hike of the AT. I've talked to and read people who carried photon's (most popular is the photon 2) for the entire trail. So don't take that to imply too much. That being said, we've night-hiked with the elights on the north-country and baker-trail's (famed for being hard to follow). I've hiked down mountains at night in the rain in the whites. Jess did Seattle SAR training with hers as well.
That being said, it's a compromise light, halfway between the traditional headlamp with AA batteries, and the photons. If you plan on bushwhacking at night, or caving (though it makes a great secondary cave light), it's simply not bright enough. Most of the trails mentioned above were not that hard to follow, and the baker trail has reflective blazes.
The Elight is 0.9 ounces with battery, has flashing and red modes (with seperate red LEDs for battery life), and is a headlamp.
All in all, it's a wonderful do-it-all piece of gear if you like your gear light, but a bit dim for planned night-hiking, a bit heavy/excessive if you're SUL'ing it.