I've been enjoying these lately. Very distinctive sound signature, extremely clean and airy, with great coloration on the high frequencies.
I don't think these serve well as your main rig, but it gives you a special mood (which is hard to describe) that is not able to be achieved on any other IEMs I've heard so far.
BTW, I'm pairing these with the SONY PHA-1s, which is IMO a great DAC/AMP for apple products. It's very intimate sounding and gives the music a glorious golden coloration which makes all my earphones sound prettier than they would be with some other DAPs.