1984 300CDT..I need to have the system recharged (had the front end aligned and then the A/C had no charge). One local shop who does only A/C work says they don't convert the Mercedes to the newer freon because the systems aren't strong enough to handle it ?? A local MB tech says they only replace with the older style freon because it works better. I would like to go with the newer environmentally friendly stuff (as well as the $$) if possible. Your thoughts??