I use a "luminous" paint that I got at WalMart for painting the curb or mailbox. It's about $5 for a pint. I have a lifetime supply of sight paint.
I'm "Old School" and used to use WhiteOut on my front sights back in the day. My Off Duty EDC and BUG have this paint on their front sight. My S&W 686 has one of those "glow tube" type sights, and except for being red, I prefer green, is a great sight too. I'm just too lazy to change it since I don't carry the dang thing.
My "bottomfeeders" have Night Sights, but I think that if it's too dark to see your sights it's too dark to identify your target. Hence, I keep a Surfire next to my bedside gun, which is my Off Duty EDC.
Biker