There is one review on Russian audio forum, quick summary:
1) Treble sounds detailed, but tiny: hats and drums sound weak, as if drummer hit them with not enough force. Overall, high frequencies are clean.
2) Mids are good, not as sharp as BA usually makes them sound, though they sound a bit recessed.
3) Bass sounds like subwoofer with phase inverter: attacks are meh, some texture loss here and there, but overall low frequencies are ok, this is not a usual anemic BA bass.
4) They are really v-shaped, meaning that treble and bass will overpower mids.
5) Sound is too analytical, separation is too much (well, for the reviewer).
So, they aren't that much better than usual 300$ IEMs.
And one more thing that everyone on that forum said: they are really, really source dependent. Probably because of their very high sensitivity.