>>One of the things I haven't seen here is how people might define the Superfly in relation to the Presence.<<
I've had a pair of Presence in my own system for more than a day during a Zu Los Angeles tour. Presence was not a "Griewe" model speaker but it was sort of a "Druid with Sub" in that it had a single FRD and supertweet, ala Druid, with a half-Definition sub-bass array. It was the least jumpy Zu speaker but had near-Definition levels of deep bass performance.
Presence sounded very smooth, still retaining the overall euphonic "darkness" of the Druid sound, but never sounded quite as light on its feet as Druid. Overall, if amplified well, Presence scales and is quite complete in the music it can represent well. But being fairly flat down to about 30 Hz, Superfly's bass has none of the trace disconnect between main driver and integrated subs, and has plenty of bass energy for most domestic rooms. Superfly will sound faster, jumpier, more vivid and immediate than Presence. Presence will sound more relaxed and stately and more euphonically shaded in its tone.
Presence is larger and more difficult to accommodate in many rooms. It's $8,000 vs. $2,600. I do much prefer Presence to Essence but also prefer Superfly to Essence. Presence was more Def Jr. than Super Druid, so a lot of its advantage is in laying the solid foundation of truly deep bass if your room can make use of it, while the main band had all the great tone and focus attributes of Druid. The X factor here is, how would Presence sound with the Superfly FRD and appropriate revision to its supertweeter and associated filter? Presence upgraded in Superfly fashion should be formidable in its own right and clearly better than Superfly alone, including for reasons of the broad, smooth front baffle.
Phil