I've tried night sights, after a bit of shooting they smoke up a bit and don't work.
I went the CT laser sight route. They work. If the "smoke" bothers you, you can normally still see the red dot. Then don't work real well in bright sunlight, but then you have your sights.
You see a lot of comments about laser sights batteries going dead as the reason people don't want them. So what IF they do, you still have your sights. Those batteries last a long time, I shoot a lot, and never had a battery fail, but if its a concern, treat them like Smoke Detector batteries. Change them twice a year when you change your clocks.
But yes I like to have the ability of being able to shoot in low light conditions.
Plus, the laser sights are great for dry firing. When dry firing, even though the gun doesn't seem to move, you don't know what's going on at the target. You dry fire with the laser, you can watch it jump around and make necessary corrections. You don't get that with night sights.
That, dry firing alone, to me is well worth the cost of the lasers. Plus with lasers you don't need to have a conventional shooting position. For example, one evening, I had a rattler under my steps. I couldn't get a good sight picture. I stuck my 642 under one step, and looked through another step. I couldn't even see the gun, let alone the sights, But I did see the dot on the snakes head was able to dispatch it. I couldn't have done that with conventional sights, nor the night sights.
But like I said, I still have my sights, I have the option of using either.