When I took it out from the box, I was surprised how light it is. Very2 light. Probably the lightest full size reference headphone I ever tried. So overall, it is very comfortable, although the cup is not as big as the comfy HD800 cup.
Build quality is good, but design wise, very utilitarian design, IMHO AD series looks a little nicer. Like R70x is saying, I'm designed by engineer for engineer. So, not aesthetically as beautiful as MSR7 or the Wooden series. But it is lighter than them, therefore more comfortable for long hours of use.
Thanks for the impressions and pics! I'm really excited for the r70x now