I hope this is not a COC violation, for a prodcut plug, but I have nothing but good things to say about these shotgun sights.
My local gun shop sold my father one because he wanted a low profile green fiber optic bead for his shotgun. His shooting really improved with the Easy Hit fiber optic bead. The best part is the bead cures you of having your head lifted while shooting and allows for fast target acquisition.
Since Dad bought one I have added it on other three shotguns and it has really helped my shooting too.
Anyway, just wanted to pass along the info.
I used Hi Viz fiber optic sights on the last Mossberg I had. That was my first experience with fiber optic sights, but I must say they worked really well. The set I bought came in a kind of kit. It had three different colors (orange, yellow, and like a neon red) and each color had a three different sized sights (small round, small triangle, and bigger triangle). I preferred the bigger triangle in the neon red/orangey color. It was extremely bright. The set was only $14 at Wal Mart. It's a decent alternative to a tritium front sight especially for the money(although fiber optics don't glow in the dark).