Well. I did a long listen today. Did some back and forth swapping to the Polk LSIm 703's. First thought with no sub is they are extremely bright but detailed. So I added in my sub and turned on the sub controls on the Parasound P5. Cut off at 80 and then full on the KEF's with sub. Much better blend on full for the main and 80hz for the sub. When compared to the Polk... The Polk are more balanced and full. I actually like the Polk better after a full day. I was really impressed with the Polks from the start however.... These are both brand new. So no run time yet. Tomorrow I will see how they compete with my RAAL towers. Bottom line after one day. Not impressed at all. Need more time. Maybe my equipment isn't a good match either. Maybe tubes. Or even maybe set up my Marantz gear with them since they are much warmer sounding equipment.
I, too, did not care for the ls50's. I recognized that they did lots of things very well, but felt like ambiance was lacking.
Much of the music I listen to is stuff like Melody Gardot or Norah Jones where the sense of a piano in a room is important. When I closed my eyes, I could envision I was outside of the room listening to the music through a large, open doorway. My best take on this is that much of the room reflections were missing, which I would venture to be the effect of an aggressive wave guide (the mid-woofer cone acts as the wave guide for the tweeter). Something like a trumpet, that primarily projects sound forward, sounded very good on the ls50's.
The imaging is truly incredible. I liked the look - anodized aluminum drivers and form factor with the spherical contour to the baffle.
In retrospect, I wish I had kept them another week before returning them. I would like to try them closer as near-field or desktop speakers and also with some less acoustic music (where room reflections are not so vital).
The Martin Logan Electrostats I recently bought have opened my mind to appreciating a presentation that is radically different, although not necessarily worse. Their artifice, as I perceive it, is that if you were to have a well recorded finger snap, it would be
too crisp and
too vivid; however, they do so much other stuff wonderfully. If I focus on T's and K's and smacks of lips, they just don't sound real, but after focusing on their other qualities, they are delightful to listen to and it is much more interesting than having roughly identical sound to my other good speakers!
After this experience, I would like to re-assess the ls50's!
Good luck!