Never have...of course I don't think I've seen the bead on any of my guns in years, I actually knocked the bead off my gun at some point last season and noticed it was gone when I was cleaning and putting it in my gun safe. No telling how long it had been gone...but I do hunt and shoot with some guys that swear by the TruGlo sight (the one with a tube on it, so you can't see the dot unless your head is in the right place). This has a lot to do with how you shoot, and how well your gun fits.

One of the fellows that hunt with us shoots with a Rueb (I think that's the right spelling) and swears by it. I think the Rueb is pretty close to the Leader at least in concept. I just find that any type of focus on the front end of a shotgun slows my swing and I start missing. Good luck and I'll be interested to see what you think of it.