I received my Miracle(s) approximately two weeks ago and can make something of a preliminary account of what I hear. I can say without reluctance that the Miracle's are technically far more proficient than any of my other mainstay iem's (Sony EX1000, SM3, CK10, RE262, TF10, DBA's, UM3X).
The very first thing that struck and continues to impress me is a sense of tonal balance. At first I thought the Miracles were a tad warm, but have since determined that they output precisely what they're fed. In comparison I have found the EX1000 thin and bright, the SM3's thick and veiled. The Miracle sound is weighty and dynamic, a bit V-shaped, but extremely refined. As for the presentation I would call them disciplined rather than aggressive and attacking. I sometimes get this feeling that at any moment the shackles will come off and the Miracles will reveal their real power, but alas they're too humble and cultivated for that. If asked to make an analogy I would say the Miracles are gentle like a tamed wildcat, but effortlessly powerful (resolving) in a way I have never heard in an IEM.
My music tastes are broad and I am a proponent of the certain-iems-for-certain-genres camp. The Miracle is no exception to this rule. I still prefer the SM3's for vocals, CK10's for rock and TF10's for mindless fun. I prefer the Miracle with female vocals over male (I find them very slightly recessed in the 300 - 1.2k area) and generally prefer the singer placed forward in the soundstage, something the Miracle does not always give me (they're not a stage monitor after all). I should add that the sound has changed in the two weeks that I've had them. Upon receipt they were more recessed, but the mids have all but caught up and is on a near even keel with the rest of the spectrum. To give an idea of what I have been listening to over the last two weeks:
Sigur Ros
Alison Krauss
Amandine Beyer
Bon Iver
Andrew Bird
Andy McKee
Arcade Fire
Sufjan Stevens
Wilco
Michael Hedges
Norah Jones
Joao Gilberto
Stan Getz
The Miracle comes out principally for acoustic, some jazz, classical and some ambient, When it comes to classical and guitars I find them untouchable (especially as the Miracles are considerably more dynamic than any other IEM I own). The imaging and especially texturing is either the best I've heard or certainly top three. I believe the greatest compliment that I can give the Miracle is to say that I enjoy them equally to my desktop setup (W4S Dac 1-- Zana Deux -- HD650). I should add that I go CLAS -- Meier Stepdance/Pico Slim -- Miracle.
Before receiving them I remember thinking that there has never been a headphone that I found perfect with all music. Prior to the Miracle the SM3's provided the most positive qualities in a single IEM and they have been surpassed. The Miracle gives me at least 35db of isolation (while I don't have the ER4S anymore I'm certain I get better isolation with the Miracle as I asked for longer stems), the most balanced tonality and most dynamic, revealing, and refined sound that I have thus far heard in an IEM. Also, the soundstage as a whole (W x D x H) is more spacious and the imaging pinpoint and holographic (rather than left/right as in EX1000); these are all things I prefer. In short I found them to sound like a $1000 IEM and once I adjusted to their slightly distant presentation (think 10th row of a concert hall) I also found them impossible not to admire.