Got a chance to hear these at an audio show a few days ago and in short, they suck. I'd heard the Stax amps are less than ideal so I did plug them into the Mjolnir audio amp at the Audeze table which improved things but not nearly enough to make them listenable.
My main problem with them is they suck at dynamics & impact, especially in the lower midrange to bass region. Metal, rock, reggae, anything with kettle drums, all that stuff gets ruined since there's not nearly enough weight or impact down low. There's also some kind of wonky resonance in the midrange & treble which pops up from time to time, it sounds a bit like the cuppy or slightly out of phase sound you get from most closed headphones, not nearly as bad but still enough to annoy me.
Didn't pay much attention to soundstaging, imaging, or detail & resolution. There were just way too many issues with the frequency response & lack of dynamics for me to really care about that stuff. Overall, I'd have to say it was one of the bigger disappointments I've had in the headphone world.