It is fortunate for me that I lack a golden ear. I listen to my decidedly mid line equipment- nothing bad, but certainly not true audiophile stuff- and think "hey, that sounds really good!". If a switch out gear I usually think "hey, that sounds really good!" Now maybe it is because I'm going from say, Pioneer to Marantz and the build quality is similar, but I can listen to some of my vintage tube stuff and think "hey, that sounds really good!" as well. It might sound a bit different, but I just don't hear much difference between any off it. Speakers change things the most for me, but the it is mostly a "different" sound rather than good/bad.
But no matter what I listen on, Britney Spears never sounds good... why is that??