No introduction is needed for this pair. The "rumours" about the sound quality are true. Some people disagree that they are good for music production, but I am not using them for this reason, so I cannot comment on that. When I am listening to music I prefer it to come to my ears as the musicians and sound engineers intended to, and I think that these headphones are doing it to a great extent.
 
Some people also find them to be uncomfortable. Well, they are not as comfortable as HD 598 for example, but this is to be expected from a closed-back pair. I would not expect more comfort than what they give. I'd describe my head as medium size, so people with large heads may find them a bit more uncomfortable.
 
Overall, very, very highly recommended!

The sound quality of this thing is absolutely amazing! I understand why some people are not very happy with the user interface, but if you spend 5-10 minutes to navigate through all the options I am sure that you will figure it out.
 
The price is a bit high, but I think that spending a bit more for something that will stay is better than going for a cheaper option that you may not completely satisfy you.
 
People also have complained about the lack of internal memory. Personally, I prefer it like that, as I don't have to erase/transfer new music all the time.
 
My only two (minor) problems are:
 
1. It does not show the time. It is not that important, but it would be a nice to have feature (if supported by the hardware).
 
2. The battery life is a bit weird. Either the indicator is not very accurate, or if you don't manually turn the device off, it stays awake even if no music is playing for hours. There is a "sleep" option that I did not have the time to try yet, but it may be doing the trick. Besides that, battery life is quite good.
 
Overall, it is a great product. I highly recommend it if you are after sound quality on the go and don't mind a little old-fashioned interface.