On that page:
Typical Battery Runtime: ~1 hour (manufacturer rated)
And a review:
Originally Posted by MiniSniper
Pros: The threads are decent and the anodizing is good. The reflector and glass are clean.
Cons: While the light is bright at first it quickly dims. I thought this was just a bad light so dx sent me another one and it had the same problem. I took out the led and found the problem. To keep the led base from shorting out to the light housing they stuck a piece of plastic between the led and pill and this does not allow the heat to dissipate and thus the led dims because of over heating. I took both lights apart and used some thermal tape to Isolate the led and it is much better now. The piece of plastic looks different in both lights and it look like a piece cut out from a isolater that fits between the led and reflector to keep it from shorting out.
Other Thoughts: Not sure how long the led will last if you don't modify the heat sink. The led should have been on a isolated round or star board then installed and but it's not.
Bottomline: I don't suggest anyone buy this unless you plan on modding it.
Not sure if I'd call this one a legitimate alternative.