Out to 25-35 yards (well withing MOST defensive scenarios), I'm most comfortable with a bead. Much beyond that, and I'd prefer ghost rings. Rifle sights are fine, but I'm a little slower using them.
As a brief aside... earlier this week I patterned some low recoil #4 and 00 buck, along with some 1 oz slugs in my HD shotgun. The last time I'd done this, I'd shot the gun like a rifle, and was carefully aiming. It shot much higher than I would have liked.
This time, I pretty much ignored the sights and just shot it like I was shooting at clay targets. Lo and behold, it was patterning exactly where I wanted it to. In fact, I was playing around with a mixed load (2 shells of #4 buck, followed by 3 of 00, followed by 2 slugs). On a fresh sheet of paper at 15 yards, the two #4 shells patterned about pizza-sizes right in the center. All of the 00 went into the center of that pattern, about the size of a saucer, and the slugs went into the middle of that, just a hair to the right of dead-on center. I wasn't "aiming" per se, I was just watching the paper and shooting as fast as I could.
Several iterations of this exercise provided similar results. So, based on this experience, I'm totally happy with the bead, and probably wouldn't notice too much if the sight was gone altogether.