Has anyone out there used Enviro-Safe Refrigerant? They claim there is no retrofitting and fully compatible as a "direct drop in replacement with either R-12 Freon or R-134a systems". When I attended the Chevellabration last June in Nashville, I talked with a guy that swore by this stuff. I just wanted to know if there was anyone else out there that has tried it. Just sounds too good to be true!