I guess I probably made this light sound worse than it is. But if you like bigger lights, it's really not a bad way to go. For $30, it's probably the best combination of brightness, long runtime, and quality construction you are going to find. And although 1x18650 pocket rockets are considered more hip by most flashoholics, unlike those lights, this one does NOT have to power down from its highest setting in order to prevent the light from baking itself alive.
LOL
Correct, if it STARTS out dim for its size, it really doesn't need to get dimmer to avoid problems.
I will say that I finally tried the 3D version, and its at least putting out enough light to be useful...its just ENORMOUS for the amount of light it gives off.
On a lumens per dollar basis though, its not too bad as a purchase, and if using Nimh's instead of Alka-Leaks, the cost of using it would not be too bad.
So, if you don't need to carry it around/EDC it...say it sits in a boat or by the door, etc....and you want an el cheapo light to fill the duty, I think its not bad really.
If you want to go hiking/carry a light with you of that lumen output, well, its a freakin anchor compared to the li-ion alternatives...but 600 L in your front pant pocket means spending ~ $45 much for the light, but that light will weigh closer to the weight of one of the three giant D Cells in the Defiant....than it will to the weight of a loaded 3-D Defiant. For the weight and size of the 3D Defiant, a li-ion powered light could be pumping out a few THOUSAND lumens instead of a few hundred.
So, again, the 3D version at least can be worth it I think, for some uses/cost benefit scenarios.