Hey, you forgot tin and silver! They play an extremely important part, too, even though most of the tin and silver don't really show in the picture, since their bulk sits between two copper cylinders. But yes, you will find no metal snobbery here! The PTFE, on the other hand, isn't metal, so who cares about it? 
Just for giggles, I went ahead and increased mine to 130. Although a number of my tools can run above 90 at the delivery point, I find 90 PSI to work well enough, so I don't see the need to push it beyond 130 in the tank, let alone all the way to 175.
Me, I find I really like a boring life.
I want to be sure to thank everyone for your suggestions. They were all valuable, even though in the end I did not follow them all. I did consider each one carefully, and I suspect virtually all of them may come in handy in the future.
Just for giggles, I went ahead and increased mine to 130. Although a number of my tools can run above 90 at the delivery point, I find 90 PSI to work well enough, so I don't see the need to push it beyond 130 in the tank, let alone all the way to 175.
Me, I find I really like a boring life.
I want to be sure to thank everyone for your suggestions. They were all valuable, even though in the end I did not follow them all. I did consider each one carefully, and I suspect virtually all of them may come in handy in the future.