about #2 you said it got noisy but didnt notice lack of cooling. Did you turn it off or did it turn off on its own? A unit with no refrigerant in it will not run or cool, so I doubt the techs finding that it was empty if you turned it off when you heard the noise. Unless the leak was so bad it lost the charge between the time you noticed it to when he arrived, which in a rubbing type leak I would doubt if you didnt notice lack of cooling.