I like to wear a visor under my helmet. Basically a short visor like a cycling cap without the cap part. I ride with both black and white, and I feel like I like the black better, but I also think it looks better, which is weird I know, but don’t judge me because I am acknowledging that I might be biased. 

Other than black absorbing more light and thus heat, is either better or worse for vision, including fatigue?

And if so, does that only apply to the underside?