I still think that Medical O2 being compressed and charged into a bottle will not contain any H20 to begin with so I think at any pressure, 500PSI or 50PSI there is no water present.
I may be very wrong, but until someone can verify this with absolute refernce to something we can all see for ourselves it is most likely to be a myth.
A Chocky Frog to anyone who enlightens us otherwise!
Cheers
J
