Saw these awhile ago but at over $200 I passed not only because of the price but also because of the mount requirements and the activation system.
Mounting it requires you to remove the extended mag tube. You lose two rounds. On a shotgun some might not want that. Activation wise, there is no remote paddle switch. There are two rubberized buttons 180 degrees apart that you click on and click off. Please don't put your hand over the muzzle.
Positive wise, it is slick as shit, and while only 350 lumens the light in white and centered. Plus, like all things Steiner, it is built...overbuilt...beautifully made. Check out their red dots and lights. Kick ass shit.
Steiner is blowing out these for $55 shipped. Had to try it for that.