I bought a Rodenstock Omegaron 150mm for less than 150. It looks and works like new. I am not sure how different it is than a Rodagon. I wouldn't necessarily make assumptions though. I bought a relly nice looking Schneider Symmar off e-bay and found it was single coated (I only looked after reading an artical in View Camera Magazine) the serial number was just a little shy of the midyear shift to MC.

BTW I have two Nikkors that I really like. The Rodenstock is EASILY as good though..