todd e and wforwumbo, one of my main things these past five-ten years has been to do research on early recording equipment and techniques from the past 100 years. The first generation of condenser microphones were all omnis, or (since they were so large, but were pressure transducers) omni in the bass, with the pattern becoming narrower as you went up in frequency. When figure-8 and cardioid condensers were invented in the 1930s, the new thing that was said about them was that their directional pattern was consistent across the frequency range, and they were recommended for recording in less-than-ideal acoustic spaces. What you've said in both of your last two messages reminds me very strongly of that nearly 100-year-old way of looking at things, and I think it still holds water.
Precise localization is a neat trick, and the manipulations that can be done with coincident stereo recordings (such as M/S) are very useful sometimes. But in terms of feelings, of the sheer "listenability" and attractiveness of a stereo recording, the thing that gets most people going is tone quality, while the thing that gets most people going about stereo is spaciousness. For me the MK 21 is a kind of ideal--I dislike the phasiness and indeterminacy of spaced omnis, especially widely spaced, and the so-called "wide cardioid" pattern offers most of the smoothness and ease of omnis while allowing a relatively closely spaced placement with decent, stable stereo imaging. But I rarely find locations where the reverberation balance allows me to use it and still get adequate clarity when larger ensembles and orchestras, etc., are involved. Much more often, the MK 22 and MK 4 (and still sometimes the MK 41) have been the best overall, practical solutions for me.
--best regards