I tried one out that some guy had at the range. It seemed to work well, but upon further investigation I noticed that it was attached by a tie wrap. I dont think I would like that, if you bumped it, it would move on you. Its a neat Idea, but I would just use the regular level. Plus his was way to sencitive. You would just about get it level and then and touch the trigger and the light would change braking your concentration for the shot. It drove me nuts. But he seemed to like it, and thats all that matters.