16bit and 32bit color actually have no difference to me.. I see both of them as many many colors, so it doesn't register in my eyes as much different. I'll have to admit that 16-bit looks a little fuzzy half the time. Since I play most of my games on my geforce2's tv-out feature, the screen is so fuzzy that there is pretty much no difference.
I would never sacrifice looks for performance..ever. It's just me. I know for a fact that our current gaming and 3d worlds will never become similar to "ours". So, why NOT make it look fake?!