"I
just picked up an XD."
"Sweet, what model?"
"9mm, the 4 inch. What sights do you think I should get?"
"It didn't come with any?"
"What? No, but it doesn't have night sights."
"You don't need night sights."
At that point he looked at me like I was eating paste right out of the jar with a severed chicken foot. I had just told him that he didnt need night sights. I had apparently disappointed him and America.
The point of the story is that the thinking behind sights has not necessarily caught up with the technology and because of that, there is a lot of ineffective, inefficient or just plain stupid information out there. If you have a weapon light (or a handheld), the need for night sights is effectively zero. The use of a light will backlight your sights, making slight alignment comically easy. I have a lot of different sights from a lot of different manufacturers. The differences between them once we get past the "do they glow in the dark" conversation is very little or quite a bit depending on what you want your sights for.
So no, you dont need
night sights, what you need is a way to quickly transition between three
focal planes while shooting and have the greatest degree of contrast possible
between the front and the rear (without blooming in your vision) to make fast
target acquisition easier. For some shooters, this may mean night sights
though for the human eye, a color contrast will serve far better than a light
contrast. I lover gear as much as the next guy; I own a few Arcteryx
products so that qualifies me to talk about the dangers of gearwhoring (no, but
Arcteryx products are actually worth it if you need them). If you are new
to after market improvements, are looking to upgrade your existing sights or
simply want to experiment, do your research and make some wise choices.
Just because a gun doesnt come with night sights doesnt mean it actually
needs them.