A review I think, but I can't read Korean
http://www.ohled.com/board/forum.asp?rn=20100212001
In studying these the two beams, the M2S doesn't seem like it will throw any better than the M1X. That said, it's obviously still a good thrower and puts more lumens downrange.
Bugoutgear
For those that asked...
Here is some info on M2S' High Mode Protection:
The SST-50 LED emits a large amount of heat at this setting. This heat may reduce the lifespan of the LED, so after 3 continuous minutes in Max Brightness Mode, the M2S' built-in temperature protection circuit will automatically activate and enter protection mode, which will reduce the output to approx. 480 lumens (Mid Mode). If the user wants to resume Max Brightness Mode they can turn off the M2S and turn back on again, the light will resume Max output.
I have no problem with the logical thermal management of a light such as this. In fact, I think it's neat that we are able to boost a light temporarily above it's sustained output capability. The problem with the M2S is that its thermal management is not logically or intelligently controlled. Instead it's more like and "idiot light" on a dashboard that does little to preserve the integrity of the component. In other words, an operator in theory could just keep turning the light off and back on every 3 minutes and still exceed the thermal boundaries of the LED. Likewise there is absolutely no reason for a light like the M2S to step down when the user is operating it in arctic conditions or even a 15F day in Flagstaff AZ for that matter. I would be far more interested in a light with active thermal management, even if it cost a little bit more. The Wiseled Tactical for example uses active thermal management and only steps down when thermal conditions dictate that it should. That way users in cold climates can take full advantage of what the SST-50 as to offer. Also, users in warmer climates wouldn't be shut down unnecessarily or annoyingly early either since it wouldn't step down until needed. This seemingly randomly chosen 3 minute is a very low tech and generic way to address the thermal issue, which really seems to be out of place on a $200+ light.
I could probably be convinced otherwise if I was to see M2S heatsink temperature readings at 3 minutes vs. the continuous runtime temperatures of the M1X's heatsink on sustained high. Somehow I doubt that the SST-50 is generating the same temperatures at 3 minutes that other Jetbeams are allowed to run continuously at and thus I feel that the M2S has been needlessly handicapped in Jetbeam's addressing of this issue.
As a long time JB fan it labors me to point out that it would be nice if they had thought this through a single time rather than to eventually have a M2S version 1.4 like we went through with the M1X. I for one would like to see active thermal monitoring. Is this type of a circuit really so difficult or expensive to incorporate into a light such as this? I'll probably have to pass on this purchase if the 3 minute "idiot light" circuitry is to be the final rendition of this model. In speaking to other less knowledgeable flashlight fans at work, all are very underwhelmed with the 3 minute high as well.
Btw, my complaints are aimed at JB, not Flavio, who has been a very respected and helpful retailer and CPFer.