only heard the XVX once at Axpona and it was crap, a mess, with D'Agostino Relentless amps. it did look impressive.
i just assumed it was the room and set-up and don't hold the speakers or electronics accountable at all for the sound. maybe by the last day of the show it had improved, but i never returned to that room.
rooms at shows should only be used for positive perceptions regarding gear.