First, I would like to respectfully disagree with Krisjan's statement that, "The Vandy will be better (i.e. more natural sounding) in every sense except senitivity - the Klipsch is VERY sensitive (102 dB/watt) and can use flea-powered amps." I take issue with this both technically, and in practice, as horn loaded drivers have inherently lower harmonic and IM distortion than direct radiators, because the diaphragms move less for a given loudness. Rise time is faster and the coil remains in the sweet spot of the magnetic gap. Look at any independent tests of horn loaded drivers, Stereophile is a good source, and you will see lower distortion. Is this swamped by secondary reflections off of the horns themselves, the front baffles, etc.? That is for the listener to decide. I have made up my mind.
The Cornwalls should ONLY be used at the junction of the floor and wall, or in the corner, which is the way that they were designed. They should not be moved into the room. There are other speakers in the Heritage range that can be used out into the room, Quartet, Forte, Forte 2, Chorus 2, etc. These all have sensitivities around 95-98db as opposed to around 102db for the Cornwalls, so if your desire is to go single ended the Cornwalls may be the better choice, but if you want a bit better imaging and want greater freedom in positioning the other models may make more sense.
And while there are those that dismiss high sensitivity as an unimportant quality in speakers lest I remind them that, if a speaker is 10db less sensitive, one would have to have a 350 watt amp to achieve the same loudness level as a 35 watt amp would give. But absolute loudness is not an issue for most of us. How you get from soft to loud is, and horns are very, very fast and have very fine gradations in their dynamics. Just as they may give up detail to direct radiators, some will find that the natural dynamics are a worthwhile compromise.
And what do I mean by "scale", "weight" and "dynamic sweep"? Scale is simply the size of the image. Weight is the way the waveform launches when the speaker goes from quiet to loud. In many speakers, the frequency response subtly changes as they get quickly louder and the bass becomes deemphasized. Lags behind or down in level. A speaker with weight will hit you with the full impact of the bass as well as midrange and treble as it gets louder. The leading wave front is subjectively complete with everything arriving at once. You hear it in the concert hall and take it for granted. You make excuses for it not being there with many modern speakers. And sweep is more subjective but it is simply an emotional connection with the majesty of the sound.
Horns do not image precisely as a fine direct radiator like the Vandys do. They are less descriminating about those things going on at the edges and rear of stage. The center image is usually quite good, having tremendous body and substance, as if the body is full. But the edge definition is softer at the edges of the image without the sharp image outlines that the best speakers present. And detail is clearer on most direct radiators. I am in my local audio club and when I listen to my friends great systems - much greater than mine - I, and they, listen to the bass, the treble, the image, whatever. Horns put the presentation together in a way that mitigates that type of analysis.
But there is a price to pay. Put your hands around your mouth and talk. What you hear is a coloration. A horn coloration. A little boxy, and a little nasal. My sensory gating tends to not even notice it in my horns, but it is there, all of the time. Every minute. And high sensitivity speakers require big boxes, which are less dead and resonate more than small, well braced boxes. Rap a wood table, what you hear is box coloration.
There is one final point that I want to make, and that is that it is my belief that modern speaker design has been primarily been driven by domestic aestetics (the dreaded WAF) as well as by the audio press. The same audio press that embraced the earliest transistor gear. The same audio press that embraced the compact disc at its release, when it was not an acceptable medium for the storage of music. And the same audio press that must sell publications with the new and the newer. The flashy, the elegant. I believe that in the quest for the flavor of the month, physics and engineering have been given a back seat. The big man almost always beats the small man. There are many more Goliaths than Davids. Happy listening.