And three impressions:
HeAudio electostatic headphone w/ Woo Audio GES
"Appalachian" style music was playing on this system. The detail was phenomenal, the last time I heard detail near this level was the HE60 off a Singlepower Concerto ES back in '06. Every single layer was beautifully presented, completely naturally with no harshness. Very detailed, and still very musical, as I could still easily get the "feeling" of the music.
philodox's McAllister Massive Attack w/ Headphile balanced K340
I went into this one with the goal of finding out what made it great for Massive Attack's music.

Not quite up to the level I was expecting, but very, very cool nonetheless. Bass went rough and deep and there was plenty of detail. The K340 still sounded like a K340 to me though, with a slight treble etch and a "hollow" mid-range tendency. It was still awesome specifically for Massive Attack though.
naamanf-built 4-channel balanced Beta 22
I commissioned this build from naamanf and he shipped directly to Florida upon completion. Until today I had not seen it in person. It looked nice, but did it sound as good? Well I'm not totally sure yet. The meet conditions made it impossible to get a clear handle on it, but I did hear an obvious advantage to balanced over single-ended with my Equinox-balanced K701 with greater soundstage lift (more front-to-back and left-to-right), greater ease to the sound (more fluid), and more dynamic swing.
I'll hear much more of what this amp offers when I return home in June.