I have an E (2.5 ct emerald cut) for my e-ring and a G (1.06 ct heart shape). They are both GIA certified. I'm really sensitive to color and I could see a yellowish tint in the G even from the top, so I knew for my e-ring I wanted a higher color.
When I wore an e-ring...F (2 tcw) and G (3 tcw). Couldn't tell a bit of difference but the 3 ct was a better cut.
Not a ring but my studs are G and they look very white but the cut is ideal.
The right cut can hide a multitude of sins!
Mine is H, ideal cut. *I* can personally see the color from the side (due to the good cut, faces up white), but my sister and fiance (who did all the ring shopping together) both swear up and down they can't see any color. I think I'm just very color sensitive.. however, it doesn't bother me and I'm glad they went up in color so I could have a bigger stone!