I just tried one out on a 12-gauge slug gun this afternoon. It seemed to work pretty well, but in bright sunlight the highest setting on the red dot was still a bit too dim for my taste. Zeroing was easy, mounting was easy, thirty rounds of slug ammo didn't kill it. The field of view isn't totally round, you can see the intrusion in the lower right corner of the LED housing, but it's only an issue at first, until you are accustomed to it. I'm not sold on the idea of the on-off/power adjustment dial also containing the screw cap for the battery compartment, but it'll probably be fine as long as you remain aware of it and are careful turning it.
All in all I probably prefer it to the Burris Fastfire, which I think is its main competitor.