I would never use a carry gun with a laser. For home defense fine. Think of how a DA is going to present that to a jury. The perception is to costly imo. If you need a laser to hit your target at SD ranges you need to practice more.
I disagree. If you are justified, you are justified. If you ain't you ain't. There is no way I could hit that possum on the move 3 times at night one handed with irons. Also for those worried about the felon using the laser to home in on you; muzzle flash will give your position away anyhow.
They shouldn't replace irons or even night sights but supplement them. If you expect to use it in daylight look into Viridian green lasers.