I like them a lot. The sound is top-notch, beating my Senn HD590 and HD595, and on par with 580/600 with good equipment. They've got the typical electrostatic sound with plenty of transparency and detail. Can't compare them to the Ety's and Shures since I've yet to hear them, but based on reviews I'd say they're very close overall to the ER-4S and E5c, and better in some respects (soundstaging, mids). The treble is slightly rolled-off, but the bass is quite good. The 001 is very honest about it's bass, and will give you exactly what's there. It won't make bassless sources and recordings sound bassy, but add some eq, or put in a bassy record, and you've got some serious bass (but not too much tactile feedback).
Comfort isn't that great. They're light and easy to wear for short periods of time,, but over long listening sessions, they really start irritating your ear canal. Over time you get used to them, but at first it's kinda hard to wear them for over an hour or so. They don't isolate sound either, but I don't think they're meant to, so this is more of a design characteristic than a problem.
They also scale quite well. Out of good sources, and with proper interconnects and an AC adapter, these sound really good. Very neutral, nicely extended, with lots of air and detail.
Recommended.