Compression was always a compromise because storage technology couldn't cope, not because we can't hear the difference, because we can, especially with classical music.
I've always considered myself very fussy about reproduction quality but I'll be honest that I don't hear a lot of difference if any between the original WAV file and AAC at 160VBR.
When I re-ripped my collection following the purchase of my first Mac I did a test taking a WAV from EAC then encoding using different engines, iTunes, Lame etc. and bitrates, I found the above format indistinguishable from the WAV. Maybe I was using the wrong type of music, this was on some intense metal and accoustic tracks, I didn't try classical.
I did have a problem with my iPod photo with piano music as the impedance of my Bang & olufsen earphones caused the whooshing problem with the headphone amp to become apparent but this was solved by uograding to a 5th gen.
Could be I have bad ears of course...