Yes George, you are very informative!
Now, all I need to do is 2 things - find out where I can buy the 406A and for what price? I already had to sell my unborn son's kidney to buy my last batch of refrigerant...LOL

I usually buy from Johnstone Supply locally, but United or one of the others might be a little cheaper.

Just about all the systems I service are cap tube types. Typically domestic refrigerators, with some soda coolers and reach in coolers.

From what I gather from your above information, I can reasonably assume that i can substitute R406A for any R12 cap tube system and can make the units much colder?