Pros: sound stage, bass, comfort, clarity
Cons: non-visceral bass (as expected with BA drivers)
I have been using these for well over 18 months now. I was extremely hesitant to spend this much money on a pair of IEMs, however I can say with absolute certainty that they are worth every cent.
The sound quality achieved with a good AMP/DAC and these cIEMs just can't be overstated - they are phenomenal. In particular I really enjoy these for listening to music concerts or classical music - the wide sound stage really makes you feel like you are there. Close your eyes and the real world just disappears and you are in the front row. It's the best cure for stress.
After 18 months of putting these through their paces, I would expect any flaws to have presented themselves by now. I'm pleased to say that I have not had any flaws at all. I have listened to music across many genres and in many situations. Not once have I been let down.
My only criticism is that due to the nature of BA drivers, if you want to listen to something with a strong bassline, you won't experience the same visceral response you can obtain from dynamic drivers. You don't feel your tympanic membrane vibrating away. Instead, you are presented with a low tone that is perfectly executed from start to finish, without even the slightest hint of wavering or distortion. It's a very different way to listen to low tones but it is still enjoyable; I suppose in a more clinical way. A great example of where this is actually a good thing is Bjork's "Possibly Maybe" which can absolutely destroy a dynamic driver. The UM Miracle executes those low frequencies perfectly with no impact at all on the mids or highs. It's really something special.
One final point is regarding the sound isolation. I use these often for air travel and compared to Shure SE535 or Bose QC2, they offer the best sound isolation I have experienced. Put some music on a low-ish volume and you wouldn't even know you were on an aircraft.
Extremely happy customer here.