I used the Borg Dually (one piece) valves on our previous coach. They worked OK, but two of them would always have a very, very slow leak that we could never figure out. It was a slow enough leak, was not a real problem, was just annoying to have to keep putting air in every so often,
Eventually, I switched to using braided extensions and the problem went away. The trick is you have to find ones that are AIRLESS. Meaning, there is no air pressure in them normally, so it doesn't matter if they work loose, you will not lose any air. Only time there is any air pressure in them is when you put a gauge or air compressor on them and press on the Schrader valve.
Have been using those extensions for many years, on two different coaches. Have never had a problem with them, yet.
