It really just depends on you're primary reason for having/needing a firearm with night sights. If there's a chance you'll be clearing a building at night, you work the grave yard shift at some old dimly lit apartment complex or anything similar to that, yeah, night sites are great.
If you're carrying a firearm for personal defense and you get out and practice enough with it, chances are you're not going to even use the sites. Seriously, sit and think about this. Think about all the times you though you of needed you're firearm or wish you had it. Think about what is LIKELY to happen in your day to day like in which you will need your firearm. Now, estimate the distance in which the threat IS LIKELY to present itself. Most threats, muggings, assault, car jacking are going to occur at <12'. If you practice enough with your firearm, you should be able to point, shoot, and hit your target without using your sites.
Next it you head out to the range, set up a standard silhouette target at 12', put masking tape over your sites and fire a few rounds while concentrating on the target. You're going to hit it. Keep in mind self defense is not about hitting bull's eyes, it's about taking out as many organs as possible. If you're firing in two round burst, you don't want both rounds going into the same lung. You want to take out a lung, the heart, or maybe hit the spinal cord.
