tomcy6 surely has a point, as several posters have acknowledged: that an audio system should at the very least aspire to "reproduce the sound of real instruments in a real space," just as J. Gordon Holt stated. But... A good friend of mine (who also writes and reviews for Stereophile, by the way) is a musician and a recording engineer, and he insists this dogma is mistaken, for a simple and persuasive reason. What an audio system should aspire to do is to accurately reproduce what the sound engineers heard in the recording booth. Unfortunately, for a lot of reasons (historical, technological, aesthetic...), that sound is not necessarily the same thing as "the sound of real instruments in a real space."
My point is that Mr. Holt's principle, to which I do subscribe, is compromised by the fact than the listener cannot compensate for whatever was done by the recording engineers. If your system succeeds in making recording #1 sound like "real instruments in a real space," it will fail to do that persuasively on recordings #2 through #n. My guess is that this is at least partly why personal taste in audio equipment—which Mr. Holt rejected as a proper criterion—nevertheless comes into play.
Be that as it may, I still agree with tomcy6: solo acoustic instruments or voice, and small ensembles (chamber music, perhaps up to chamber orchestras if your room is large enough) are the likeliest targets for this aspiration. But that does not mean that rock music can't be very compellingly reproduced in your listening room, of course. A Tool concert is an astonishing assault on one's senses, but listening to Tool LOUD on a good audio system is, in some respects, an even greater treat.