The big hoo-ha over R12 came about the exact same time that the patent expired / required renual. Coincidence? now, I haven't been in the 'biz' for about ten years now, but when I was going to tech, and got my certification, there was a product called 'hotshot' which was a drop-in alternative for 12, and it was a mix ( or perhaps a blend ) of 12, 22, and something else. Now, if 12 is bad, how does mixing it with something else make it good? 12 is and always will be more efficient than 134, even if you can't spell efficient. also, it is and always will be manufactured, just not here in the US perhaps. Mexico is taking full advantage of the ozone layer fiasco to reap big profit manufacturing 12 and shipping it to whatever country is intrested. Another caveat about the big ozone hole... it was right over an active volcano.
hmmm