I believe if you read up, you will find the ES12 is not a "replacement" for R12, but is for 134a which is a "grey area" so to speak in the laws. Since I am the only one that will be working on my system, I will take my chances. If R12 was still on the shelves and priced reasonably, then yeah, I would have put it back in as it works very well. R134 is some deadly stuff, face it, R12 was a way safer refrigerant, but I won't go into how I feel about the change from 12 to 134. The ignition points of ES12a are higher at 0 and 5.5psi than 134, but I believe once you induce an oil mist, they will both go up in flames. Have you read up on HFO-1234yf? If not, your gonna love that stuff. Hell, I will take my chances with ES12a, once again, the government and auto manufacturers are worried about my safety
