I find these types of sights a distraction. One of my P-guns came with a standard white and a red glow sight installed. After giving the red sight a few rounds, I switched back to the white one. All I want to use a sight for is to verify my mount, after that my focus is on the target, not the sight. You may be the type who isn't distracted by a glow sight and won't let it lure you into shifting your focus from the target to the barrel.
Edit: Since I don't use my shotguns as rifles (shooting at ground targets), my first thoughts go to wing shooting. If you're thinking about a glow-type sight for fixed targets, where your focus is the front sight, then they might be great.