Highest Possible Sound Quality from iTunes

[Confused]

On the other hand a full computer can run ROON, Dirac, and a lot of other things which music servers can't.

I take the point, but this situation is changing I think.  For example, the Antipodes music server is now being revised such that it can run full Roon, plus there are already products like Computer Audio Designs CAD CAT.  OK, I know the CAD CAT is basically a 'optimised' PC, but most music servers are Linux based, so it's a subtle point.  The Antopodes move to incorporating full Roon functionality is very interesting because the Antipodes is Linux based.  If you then consider that Melco, Aurender and many more are also Linux based, how will all this develop?