It does help tremendously. I painted the sights of both my Ruger SP101 and Kahr PM9 similarly. Taped off the areas with blue painters tape and excess "whittled" off with an exacto knife. Cut at the point you want to be an edge and then whittle it back and off from there. Dig too deep and there will be marring. I went slowly and cut just deep enough to separate the paint and not going too far -- it's a feel thing, kind of like stripping electrical wire in a pinch with a pocket knife.
Both the SP101 and PM9 are fantastic handguns with terrible sights (I bought the Kahr used with the factory white missing from the sights) that easily get lost against each other and the target in all but the best of lighting. On both I used dollar-store nail polish to paint the front sight white and the rear sight orange. The contrast and speed of acquisition are excellent. Both sets of sights have held up to hundreds of rounds of shooting and numerous cleanings.
By the way, I've taken my rifles out shooting with the new paint configurations. I left the first one with a white front and green rear, but did the rest with white on both. Target acquisition is greatly improved through varying backgrounds, targets, lighting, and levels of smoky ammo. I even did the rear peep of my Beretta CX4. At first, I tried to paint a white circle with a border of black left between the hole, but couldn't find a good, clean way to do it. I ended up dotting white paint at 12-3-6-9 and just that little bit did wonders to help my eye aim quickly and accurately.
I haven't resumed experiments with the glow in the dark paint. Although it's high quality, it's just a too little granular to use in this situation. I may think of some alternate, larger patterns, like maybe lining the edge of the front sight post protector. Although not terribly accurate without the rear sight, a pair of opposite-facing half-moons in the dark may be enough to be effective at closer ranges. Kind of like a low-rent red dot.