I listen to Sanders speakers at every audio show. They sound really good on some content. The problem I have with them is that you always hear the signature of the speakers over the music. Everything sounds large, tall, etc. when they shouldn't.
Roger writes extremely well though. I really like his articles (which he wrote for us in another forum) on electronics, and general audio topics.
I don't know about Sanders speakers. I have not heard them. But, with my own, tall electrostats, I just don't hear the "large, tall" you describe. That is also true in comparison to other more conventional dynamic driver systems, though those comparisons are from memory in different rooms at different times, not side-by-side, but similar in some ways to how you formed your own impressions visiting different rooms at shows.
I use tall ML Prodigys up front together with a horizontal ML Stage center plus ML Claritys in the 110 degree surround positions, but up on 2 foot tall stands. The center is mounted above my TV, even extending somewhat above the tops of the Prodigies, but carefully aimed down to ear level at the sweet spot via a laser level. So, most everything except the center extends via the panels from below ear height to well above it in terms of wave launch. The horizontal center has a short, cropped electrostat midrange and a dome tweeter flanked by two small woofers, used at lowish xover points.
Since the visual cues from stats or other panels strongly suggest "tall", and since spatial presentation is a high priority of mine, I have tried to pay close attention to whether there was a sense of vertical stretching or smearing of the image. So far, I have heard absolutely none that I notice. Visiting audiophile friends concur in comparison to their own non-panel systems.
What I do perceive is an uncanny ability to portray apparent height with some recordings. I believe I can often determine if middle and rear sections of an orchestra are on risers or not via recordings. Subsequent searches for photographic or other evidence of the physical deployment of the orchestra always seemed to bear this out when I had no a priori knowledge for a specific orchestra. Again, my audiophile friends concur and remark at the phenomenon, which their own Magico, Revel, etc. systems seem unable to reproduce, certainly to nowhere near the same extent.
Last week, I attended a sublime concert at Corpus Christi Church in NYC by Stile Antico, a brilliant, young English a capella choral group specializing in Renaissance and Elizabethan sacred music. Their Harmonia Mundi Mch SACDs are among my very most precious. Playing their recordings upon returning home again revealed no vertical stretching of the image of a dozen or so point source vocalists arrayed in a gentle arc across the stage. Corpus Christi and its largely Georgian (?) reproduction interior of wood and plaster did not acoustically provide the same degree of wonderful, diffuse envelopment that their Mch recordings do, including in the vertical dimension, likely because the recording venues are older, taller, larger English churches, abbeys and cathedrals of masonry.
I also pay close attention to whether that differently configured, horizontal center channel speaker causes any imaging discontinuities at center stage, again including vertical ones, due to the mounting height of my center channel. I hear none with Stile Antico. The voices have always appeared to be in a continuous horizontal line across the frontal soundstage, just as they are in performance, and I am really glad I finally got to see and hear them live. Ditto with center imaging for small ensemble chamber groups, like string or piano trios, string quartets, sextets, octets, etc.
But, actually my recordings of Stile Antico come off strikingly well in all ways vs. my impressions from live performance. And, I cannot say it enough, their music is simply spellbinding. It was for the music that I attended the concert and it is for the music that I play recordings at all. But, wearing the other hat and analyzing the sonics is also an inseparable part of my DNA. I don't find it detracts from my enjoyment of the music itself in any way. Actually, it enhances it.
Sorry for all the anecdotal and subjective impressions. But, we are talking imaging, a topic for which we lack good objective measures.