My concern about the sights that use both tritium and fibre optic components is that every sight I've had with fibre optic parts seems fragile. (For a night sight that's probably less of a big concern, 'cause if the FO part fails, the tritium will still work.)
Sheepdogged regarding front night sight only said:
That's fine for horizontal alignment, but a rear sight is more necessary for vertical alignment at night in my opinion (though it may not sound intuitive at first). I'm also one of those guys who is always in search of the perfect setup, but I just bought an FNS with factory night sights and guess what? They're good enough, and I was pleasantly surprised.
I've had a bunch of different night sights over the years and I continue to prefer
BRIGHT ones with a white surround. The two almost-new FNS-40s I recently traded into have night sights. They're
fresh, but they're not particularly bright, and they're neither large nor surrounded by white. That is true of several other guns I own -- including one set of sights recently replaced (under warranty) by Heinie/Trijicon (Straight Eights)! With most of these (less bright) night sights, you really have to have a very dark environment for them to do much good. In some parts of your home (even in the middle of the night), and even more so outside, you're going to find that your surroundings aren't that dark...
While YOU ARE CORRECT that using the rear sight is important for precise shot placement -- I would argue that as long as you get the front sight on target (centered on the bad guy's body) you're going to hit something critical, ranging from the lower abdomen to the head. And chances are you'll be doing multiple shots quickly -- and a precise second shot is more likely theory than practice. A lot of "presentation" practice with the gun will help you get the gun where it feels RIGHT and is generally aligned front and rear, almost naturally. I'm not advocating NOT getting rear nights, just suggesting that while the rear component is important, a front-sight only can be useful, too. I suspect that many of us won't be calm and cool enough to get off a precisely-aimed shot if we ever have to use a weapon in self-defense. (I've managed to be calm and cool in competition, but THAT sort of stress and adrenaline spike is different than what you experience when you really are (or believe you are) physically at risk. In competition the only damage I suffer -- if I don't do it well/right -- is to my ego; I suspect I might have different motives and concerns in a real-life confrontation. You may disagree, and if you can do a precise shot (or shots), there's every reason to do so. (That said, from what I can read and have heard, a surprising number of self-defense situations -- when a weapon is actually used --are up close and personal, and involve something that is equivalent to "point-shooting."
If you must have rear night sights -- and I understand why that could be important to anyone -- be sure they're
bright and useful in lower light; most of the night sights I've owned were NOT! I have given serious thought to XS sights for several guns, and while they
XS SIGHT SYSTEMS doesn't show FN as one of their supported guns, I suspect they can fit FNs if you contact them. XS offers both a BIG and a SMALL front sight option, plus a vertical tritium bar at the rear. Both have a large "white" area surrounding the front sight. You connect the "dot" on the front to the rear, like the letter "i" -- you see this configuration on some SIG standard sights. For a weapon primarily intended for self-defense use, that sight design (see the picture at the link) seems almost ideal. If you must shoot targets, too, the smaller front dot is a better choice. (Folks with weakened eyes like the BIG DOT!)
https://www.xssights.com/Products.aspx?CAT=8208
Note: I didn't mention it earlier -- but the whilte area surrounding the tritium vial is generally needed most often only on the front sight -- as that's where it's most useful when trying to see the sight in bright light -- it's far easier to see the rear sights.
