The Zn IEM (zinc liquid metal) were a noticeable improvement to my V-MODA Vibrato IEM that I bought a couple of years ago - the bass is quite strong but much tighter and better controlled than before, the mids are slightly more transparent and much fuller (not recessed), and the treble slightly smoother - gone is the V shaped frequency response, and it's now a curve that's still bumped in the bass but flatter in the mids and treble.
I tested the microphone in the noisy CanJam room by calling my son's phone, and he was wearing his M-100 and didn't hear any of the ambient noise in the room surrounding me and the Zn microphone. The volume control on the IEM cable worked flawlessly, and the center control button worked for Siri when held, pausing and starting music with one click, while double and triple clicks worked for skipping forward and backwards. For $180 I think they are a worthwhile investment if you don't already have a mobile phone universal fit IEM headset.