Hmmmmmmmm
Spike-It's Plastic, Spike-It white colourant as well. Ultra Molds 2.5 Gallon stainless pots too. Minimum batch mixed is 2 gallons. I somehow don't seem to have an issue getting a nice clean bright white. If it yellows in the slightest I won't package it and put it on a store shelf. When I run these too I will shoot a few thousand a week. A lot of subtle light colours (pearls, hilites etc) too.
I firmly believe there is no such thing as the "Perfect" plastic. They all have draw backs. DON'T buy into all the hype, try as many as you can and find the one that works best for you. I have found what works best for me and just because I use it doesn't mean it will work best for everyone.