How much “suspension of disbelief do you need?”

It depends . I suspect the reproduction quality needed to suspend belief every time you hear a 'better' system. I recall stories of live/recorded demos in the 19 teens with frequency response of old telephones and many participants were heard to be amazed saying they couldn't hear a difference. Expectation has a lot to do with it.

Some recordings do a better job than others. For me one of the nearest to being there is the Little Feat live album Waiting For Columbus.  It does a pretty impressive job of capturing the space and energy of a live performance.

Two different usually wonderful ways to spend time and share experience with others. 

I don't think I'd want the full symphony orchestra playing in my music room. Where would they all sit? 

There's quite sufficient space in my Tardis.

This hobby, or whatever it is exactly, is like a dog chasing its tail. No one no where is going to achieve a Live performance in their living room. The sooner you realize this, the happier you will become.