jaferd
It seems intuitively obvious that an accurate system would reproduce the beautiful tonality of natural instruments and voices, so that's what "everyone" would shoot for.
I think this all gets complicated by the vast number of colorations inherent in the recording/mixing/mastering/reproduction chain (including speakers designs, different rooms etc). I've seen some people, who know more than I do about speaker design, explain that it's essentially impossible for a speaker to truly, accurately reproduce the original sound of instruments (different polar responses and other issues being a bugaboo). Whether that's strictly the case or not, it seems like many can do better than others, at least to our individual ears.
My ideal is a speaker that would indeed reproduce the amazingly wide variety and richness of "the real thing" (be it piano, voice, guitar, and many other instruments). Some seem to get closer than others. But as a compromise, since much of what we listen to is artificially constructed (and often sounds that way), I at least want a speaker that helps me enjoy the music as much as possible, and I'll go with a speaker that has a general "voice" that sounds generally "right" in terms of an organic quality, even if strictly speaking it's not able to perfectly reproduce the original sound.
As per my OP, I'm not wedded to only the Spendors. Not at all. I have a number of speakers that for me all capture some essentially "right" and pleasing qualities.