I pickup up a pair of these over the weekend. They have quickly become my favorite headphone ever. Yes, they are huge, heavy and don't exactly fold flat... but with that said, they fit my hard-to-fit big head really well, and have been comfortable while worn for 8 hour days.
When I'm on an audio conference, I turn the amp off to conserve power, but when I want to rock out, On+ really makes these headphones spring to life! I've been listening with a variety of genres, and probably the best sounding stuff has been hard rock. I cannot speak for many other brands in the price range, but the Mo-Fi's scratch the particular itch that I have.... A headphone that I can crank the hell out of, drown out the outside world, and get lost in my music for the first time in years.
Well played Blue!