Night Sights
Wheel-er, for an extra $100 or so people who carry a handgun for personal protection are well advised to upgrade to a set of night sights. Some are cheaper than others but most high quality pistols these days are available with an upgrade or can be fitted with night sights.
I've been carrying them on service pistols since 1993 and will never go back. Most varieties have a three dot set up in green that glows brightly to the rear. The secret is the Tritium gas inside gas vials inserted into the sights. Over time they will begun to dim but I have gotten anywhere from 12-15 years out of most of mine. Of course it is often pointed out that bad guys can see night sights as well but that would only work if they are standing beside or behind you.
There are other varieties that have a horizontal bar on the rear sight and a dot for the front sight and some companies even have different colors available. My wife's customized Smith 3914 has a set of IWI (PT Night Sights) with a green front and yellow rear dots. The purpose for the different colors is two-fold. First of all, there is no way that you will accidentally misalign your sights when you know the order is yellow, green, yellow and even easier than that, green tritium sights are the brightest with red, orange and yellow being more subdued. My wife's pistol draws your eyes to the front sight because it is BRIGHTER.
After getting off from work at night I usually walk into the master bathroom and dim the lights (a dimmer switch in the bathroom is a treat for anyone that has never thought of such a thing) and it always cracks me up that you can even see the two glowing green eyes on the rear sight as the pistol rides in its holster.
I have found that while qualifying at night, shooting accuracy is better because your eyes are more focused on the sights and the target is blurry. During the day time there is a lot more to see and take in and often times under stress or time constraints it is difficult to remember the basics; front sight in focus while rear sight and target are blurry, correct sight alignment and placement on the target and a nice steady increase of pressure on the trigger until it goes bang (no snapping or jerking of the trigger).
It is often difficult to get a good feel for night sights until you try one in a dimly lit room or a dark (bath)room. Most gun shops will probably frown on your request to take a pistol to a bathroom but if you explain what your intentions are they might oblige you.
My bet will be that after you check out a set of night sights you'll never want to go back to having a defensive pistol without them. Heck, people have been known to install them even on wheel guns. Of course those are a lot more complicated than swapping out front and rear sights and require professional installation.
I hope this info was helpful.