This isn't going to be the typical post about sound quality. They sound great easily equaling my Denon D7000 and Senn HD650's. Of course they are different from those but the sound is still worthy of the price. However they went back for credit and here is why.
Isolation: Several posts talk about how well they isolate outside noise. I'm in the gym daily and I had hoped they would do a better job than my Vmoda M100, Monster Inspiration, Beats Pro and Denon AHD1100. They did not. Outside noise was just as loud with them. At home they did no better then my Senns, or Denon D7000.
Earpads: Being in the gym daily I sweat a lot. With all my other phones my sweat just beads up on the exterior of the pads and I towel it off several times during my session. With the Ultrasones(and mentioned on their website) it is absorbed. By the end of my workout the earpads and headband felt mushy and sticky and took almost a day to dry out. I called Ultrasone in California to see if they could advise how many of these cycles of absorbing and drying out the pads would be good for since replacements are $300.00 but they did not return my message.
Supplied cords: The coiled cord with a 1/4 plug was too long and heavy. The other cord which also controls a iphone felt very cheap. The cord I really wanted comes with the Signature Pros and is available for purchase as a accessory for $90.00. I didn't want to spend another $90.00 to get the cord I wanted having spent $999.00 for the phones.