the two stage regulator is not safer. A two stage regulator is for convenience so you're operating pressure dose not drop drastically as the tank pressure declines. When this happens you turn the pressure up. They do cost more. I just twist the pressure knob, it saved me almost a hundred large. If the regulator has a male fitting its a CGA 510 and will screw left right into the new or old propane tank. If its a female fitting get the adaptor at any welding shop. I had one job where i was cutting for over a month With propane With an acetylene set up it worked great Saved us a bundle in gas and there still using it today 14 years later to this day no problems No propane specific hose.