I listened to and liked both the Sleeks and the Klipsch's at CanJam (preferring the Sleeks), and am a long-time Ety fan, but after spending time with both the UE10s and 11s (universal) at CanJam, DC, and then again at home (thanks, Dan), I'm going to disagree your statement that multiple drivers are more about marketing than about sound. Done well, which UE does in at least these models, they make a significant different in sq.
On a side note, after three months of impressions dramas (two sets rejected, blah blah), my UE11s should be home with me in a couple weeks. The weird thing is that I have no idea what they're going to look like. After obsessively emailing changes re color choice for three days, I got sick of myself and told the artist to do whatever he felt looked best while using the cat in my avatar. I'm now both excited and very curious.