Ive listened to the Jm Lab Nova Utopias with Boulder amplification and Accuphase source. (at Sound Minds in Austin, TX) I can honestly say that it was one of the best sounding systems Ive ever listened to.
Granted, it was in perfect conditions... the amps were warmed up for several days before listening, the room was well treated, the cables were big $$$ Tara labs, etc..
On some tracks, it was sounded like you were there at the venue. On others, it sounded like the solist was standing in the room right in front of you. If I were blindfolded, and you had a bass guitarist standing in the room, I wouldnt be able to tell you if it were the real thing or just the system reproducing it.