NU-22 had a 5-15% capacity loss. I haven't heard what the NU-22B figures are. I sold one of their big shots a system for his house. He told me it is now running NU-22B and doing just fine. It is sized right on the money with nothing to spare so he must not have much loss with it.
NU22B is supposed to be an improvement over the previous A blend ICOR sold. Capacity it SUPPOSED to be up considerably and they are touting it as a drop in replacement for R22.
Bring back CFCs and fuc* the guys with calloused inner arms.
410A is closest thing to an azeotrope we are going to see from the chemical companies while in the mean time third world and a lot of Eastern European countries aren't even observing Montreal and Kyoto.