I just got one from ebay, and when I put in 2x nimh batteries, the laser stays green for an unbelievable amount of time and takes forever to warm up. Once it finally turns amber, it is maybe just a tad brighter than a 5mw 635nm pointer.
After trying a 10440 battery, it starts right up in amber very nice and bright, but last only a few moments and will slowly die down to extremely low brightness, even much dimmer than a 5mw red pointer. I tried 3x nimh with same results. when I first turn it on when it's cold, it will be bright for maybe 10 seconds. But after it warms, it just puts out an extremely short burst of bright, then immediately falls down to 5mw red levels or below.
Did I get a dud? Pretty unimpressed.