Great packaging, well presented when opened and the high build quality of the units themselves are immediately evident and impressive. The connections are also of a high quality and very secure.
The sound is clear, detailed and has some width.
Unfortunately the rest is negative.. In contrast to the other review, these units do have well separated bass, but it is weak and too far from the rest of the frequency range. The mids also lack presence as a result of the poor balance between mid and bass frequencies (think of recording your voice on a quality microphone, then playing it back on a laptop speaker!). The worse thing of all is the treble though.. it is detailed and accurate, but so bright that it isn't comfortable to listen to for any period of time.
I 'back to back' listened to these with other brands and types of headphones to make sure I was being fair in my assessment. The closest set I have are Shure se535's that I ordered, and unfortunately turned out to be fakes (far too many fakes on the market!) - yet these fake IEM's ironically outperform these AS12 units for sound, and incredibly by a notable margin!
I can state the AS12 build quility is confidence inspiring with no reserve - but this is in no way reflected in the sound. These AS12's shall be returned. There is no circumstance I can imagine where I would reach for these IEM's over anything else available to me.
I shall do some more research, and depending on the efficiency of the returns service, shall try this brand again and see if I can get the sound to match the build quility - if I can I shall be very happy!