The only non-PPT enhanced system I've ever heard that came close to the kind of realism we are getting was Randy Cooley's room (Optimal Enchantment) at one of the audio shows.
If the best sound you have ever heard was at an audio show, then I don't see how I can take any of your personal listening experiences seriously. There is one thing listening rooms at trade shows all have in common. They sound bad. That is not at all surprising given what it takes to acoustically treat a room for what can be considered great sound.