I know I'm late, but just wanted to give my input since I just tried my red dot with skeet shooting. It did not make me better, but it did not make me worse. If I was forced to pick, I would use just the ghost ring sights if I'm ONLY shooting skeet. However, if a shotgun is for skeet AND home defense, I'll take the red dot.
Ps. Also should note that my "red dot" is actually trijicon's 12 moa green triangle reticle. So maybe my experience wouldn't be the same if it was actually a small red dot.