I have night sights on my colder weather carry gun, a Ruger SR9c, but that's because it's rarely carried (Florida doesn't have much cold weather) and mostly used as home defense with a taclight. I don't like the night sights that much but I already bought the damn things. 3 dot sights in general don't work very well for me.
My average carry pistol, a M&P Bodyguard .380, sports the stock blacked out sights in the rear with the front sight simply painted with a bright green model paint. It lets me acquire my front sight extremely fast, faster than my night sights. If i'm ever in a situation where I cant see my front sight, chances are it's time to pull out my flashlight anyways because i'm not taking a shot without knowing exactly what I'm aiming at and whats behind and in front of it.
Night sights, IMO, can be great when accompanied with a flashlight but I would never ONLY rely on them for targeting at night.