I've heard the Cogents several times, and agree that they are absolutely magnificent.At T.H.E. Show 2006 I took my musician son by the Cogent/Welborne room, and let's just say my son isn't exactly a fan of classical music. I don't recall the piece they were playing, but after we left he told me that he could have stayed there all day "...and I don't even like that kind of music!" We weren't even in the sweet spot - we were off to one side.
At the Rocky Mountain show I didn't really get a chance to spend any time in the room - just stuck my head in and said hello, as I had two rooms of my own (never again). But I'm not at all suprised to hear you found the Cogent/Welborne Labs room to be the most enjoyable room at the show.
Duke