rifle sights
About 30 yrs ago, I took a Remington 20" rifle sighted Rem-choked slug barrel, screwed a super-full turkey choke into it, and set about killing gobblers. The rifle sights allowed adjust the tight patterns point of impact to land exactly (well, as exact as shotgun patterns get) with point of aim. I thought it a tremendous system, and still do. Rifle sights or peeps, allow adjustablility, and a small degree of precision with tight choked shotguns, or short distances, or slugs. I had the same sight set up on issued LE shotguns by my agency, and found them superior to plain beads as well.
I do believe that a rifle sight bead /blade set up is a slower than a plain bead, especially for moving targets. I've shot a few informal clay birds with my turkey rig, and getting everything lined up just so does take longer. But at short SD distances, with coarse, flash sight picture, I doubt it would matter much.
The Rem rifle sights on my gobbler gun have held up well, and have not required re-zero, but I check the screws every season. I have seen the rear blades go AWOL on LE shotguns riding in racks for years and tightness neglected. The rifle sights set a bit high on the barrel, the front bead is a real brush hook. Brush and limbs knocked the factory white paint off the front bead long ago, and I repaint it every season, often during the season, and keep a bottle of paint for that purpose in my turkey war bag.
I have never worked with a shotgun and peep sight, but a durable ghost ring set up sounds good. I've shouldered a few factory Mossbergs set up that way as gobbler guns, but never bought one. Also, the "add-on" fiber optic sights tend to be a bit fragile. We have such a rig on bamaboys turkey gun, and while highly visible, I find myself always trying to baby them, as they are simply plastic tubes. The little screws that hold them on the rib are really tiny too. But I would rather have them as single bead, regardless.