You don't use sights on a shotgun. Nobody does. Using shotguns properly is a pure hand-eye deal like tennis or baseball: if you ever tried to watch any part of a tennis racquet or baseball bat while using it you'd never hit anything with it. With shotguns, you watch the target 100% and the gun zero percent.
I like my Winchester Model 1300 defender. It’s great.
Affordable, dependable, up to 3 inch shells if you want them.
Don’t get too fancy with your shotguns; they are such devastating weapons and have such a proven technology that the choice really is what type of action do you want.
Choose pump, and practice, IMHO.
Then what's the bead for?
I use the sights all the time with my shotgun but then again, I’m not using it like you do. I’m not shooting trap or skeet. I’m shooting targets in an IDPA manner with a ghost ring.
The next competitor complained I was taking too long to shoot my Mossberg 500 pump. I averaged about 11 seconds for twelve targets.
He missed. I didn’t.
I have to admit, I wish I had an autoloader. I can’t imagine how fast I could be without pumping the next round.