pricing of some of these audio components is astonishing, but difficult to comment unless you have actually heard the component-most extremely high price gear I have heard has been poor value for money to say the least
I remember, about 20 years ago, I heard a full Linn system in Harrod's. It sounded astonishingly good, but, at £60K, it certainly should have done. As said above, Linn certainly make a great product, but I know I'm never going to be in a position to own any of their stuff, sadly.
It's milled aluminium not metal, this isn't a very expensive process, the milling machines are expensive, but they will last a couple of decades. The company I work for has similar machines milling billet aluminium for components.