IMHO the M2 bezel does offer some vibration and impact damping in all axis, but more in the fore/aft directions. I'm not about to test it though, so my opinions are just based on understanding the mechanics of the assembly.
You can kind of see how it works in my vid...
http://www.youtube.com/watch?v=WunPPjKOb3U
An LED
circuit can be just as susceptible to shock impact as incandescent. I have a really solid and hefty feeling Inova to prove it. It now behaves more like a flickering candle than a flashlight after just one drop:candle:. So depending on how abusive you are it could be a worthy investment. While the LED emitter is more robust than an incan filament, the added circuitry of a regulated LED light adds complexity and increases potential for a failure. Compared to an unregulated/direct drive incan.
There are thermal limitations to the M2 bezel that make it only moderately suitable to host an LED. The foam rubber component in the bezel traps heat, so if you are running a high current module you run the risk of overheating the emitter. Periodically I use a solarforce multi mode in mine It draws 150/350/650 mah. I like using the lower two modes (40/80 Lumens) to keep emitter temps down. But I usually use it as an incan host, the way Paul Kim designed it:twothumbs.
How well the M30 works really depends on how much heat the emitter creates.
The other thing you have to watch out for is the foam/rubber sleeve in the bezel does NOT create a SOLID/rigid contact between the pill and body. So I have to retain the large outer-spring on my solarforce module. That further (IMHO) limits the amount of thermal cooling.
IMHO you are better off using a different bezel if you are running high a high current LED. But an M60LL (those draw... what?.. around 200 mah?) would be right at home in the M2 IMHO.