Gear,Concerning my old and failed regulator/ meter, the tank valve was turned off before storing and no, it does not leak. The welder sat for a few months. I went to use it and the weld bead was horrible. I asked the old grey hair next door for help and advice. He has welded for a living for the last 50 or so years. That's all he does is weld things. Aircraft, medical, NASA, Government, and whoever else needs welding done.
A very good guy I might add too. Anyways I digress.... He fiddled with it and tried to do a few beads on some scrap. Then he asked me about purging the pressure off the regulator before storing the welder. I said it was not done. He laughed, told me what went wrong and why, and got me a new regulator from one of his suppliers at an awesome price.
The rest has already been told here.
Oh by the way I never zero the meter with the knob before storing and it has never done anything bad to it either, as instructed by the good welder guy next door.
In this hobby as well as any other endeavor you'll find different ways of doing things and often opposing opinions. It all depends on what works for you. Your neighbor may well be correct, or simply telling you what he has experienced which is obviously different than what I have. Neither of us are wrong...just different.

Your advice is always respected and anyone reading this should make his decision based on what he believes is right and more importantly, what works for him.
Tom