These are a wonderful shade of teal green, very subtle in difference to the Emerald color. I would say that for those that are having trouble noticing the difference, Quetzal is more blue toned than Emerald, but I agree the hues for each color chosen by PP are very close and easy to mix up. Sizing seemed true to the size I needed; I will say that these go by dress size instead of something like pants or brief sizing, so others may want to size down from their dress size [unless you are larger in the thigh than is typical for your shape] as these should fit like your briefs fit you.
The material was soft as all get out, but boooooy, are these delicate as hell. You'll need to be extra, EXTRA cautious when handling these as they will rip at the slightest hint of anything sharp, rough, snaggly, just anything and these will run so badly and gain holes so large that it will tear sections of the stocking off in odd amounts. They also pill quite badly at the top hem section and all along the foot/ heel.
I like these a lot, but it is hard to justify the full price when they are so freaking delicate and pill so badly.