Earlier quoted context omitted.
Does it make a difference? It certainly sounds different (on my very midrange Audioengine speakers). I certainly can't consistently identify which one is lossless in a blind test, but there is an audible difference between the same song in Vorbis and FLAC. I don't know how useful this distinction is though.
The differences are due to psychoacoustics - https://en.wikipedia.org/wiki/Psychoacoustics . Our perception changes depending on situation, time, you knowing what is played, etc. To say that you hear a difference you should succeed in a blinded test and without any delay between listening. And succeed not only once.
Then I guessed "same or different" quality. Got about 85% right overall.
I'm sure it wasn't perfectly blind, but seems to indicate to me that it does in fact sound different. Now, I cannot say for sure it's not sound cards or other things in the output path causing differences as well.
Now if you asked me to pick which was HD and which was 320, I did worse than random. So I am not claiming that HD sounds "better", just different.