Just had my Sonorous IIIs arrive, and after an hour of listening, here are some initial impressions.
Comfort is fantastic. The earcups could be bigger/deeper, as they don't go fully over my ears unlike my MSR7, but that's okay, as for something advertised at 410g, it's very easy to wear for extended periods. Grippage is very light too, but sufficient to get a good seal.
The cable is easily one of the best I've ever touched, so smooth and rubbery yet nothing too heavy, it inspires confidence in the user that it'll last for a long time.
Onto the sound, first thing thay catches my attention is how open and airy these cans feel for a closed back. The openness sounds close to that of the HD598/599, decently wide and with sufficient depth, but nothing on the level of the HD600 and up. On certain studio or live recordings, I can place instruments and fairly accurately, and it does so consistently.
Next, the overall signature comes to me as a neutral/mid-biased to slightly warm. Vocals are the main focus here, sounding very clear yet with some distance from the listener. Bass is quite light, but has good quality. Definitely could be punchier for my tastes. Treble extends very well, but is quite laid back. Detail retrieval in the upper mids and treble is stellar.
Overall quite an interesting pair of headphones, one that is good for the likes of soul music/jazz/acoustic music, something to kickback and relax to. Have yet to try my whole library so it'll be a while before I do have further impressions.