My eyes have definitely changed over the years, and by change, I mean they suck....lol
I used to be able to shoot a handgun pretty reliably with whatever stock sights came with the handgun....not anymore......over the last two years I've either installed fiber optic sights or had them installed on literally every handgun I own. I used to have night sights on a few of my handguns but I've since gone with fiber optics on those as well. Nowadays, the white dots that a lot of handguns come with I can barely see them. I've tried several different colors but red front and green rear are definitely the fiber optic colors that my old, tired eyes pick up faster than any other color. The rear ones don't really concern me that much, I try to focus on the front sight, but that red front definitely gives me a good focal point.
I will also say that the red front fiber optic sights that Springfield Armory puts on their XD mod 2 series handguns are very high quality, I've very impressed with my XD45 Mod 2, it has a great sight picture.