Feature:
The headphones come with a detachable gold plug thats very handy. Wires and plugs tend to stuff up after time and youd be forced to throw the whole unit away, however with these you can just get another cable/plug.

Quality:
i have had these cans for about 2 years . they are still in perfect condition. build quality is excellent.

Value:
yes. if i ever lose these or accidently run them over with the car , i would by another pair the day after.

Desirability:
they do like abit retro, the first time my bro saw me wearing these he laughed and said what the hell are they. They do look abit big and old recording studio style looking, but there is a reason why they are kinda biggish because they pack a big punch.

Sound:
The best. Awesome. Worth every penny. I spent along time looking for the best headphones suited to my style of music which is trance and rnb. I have owned a pair of sonys and koss headphones in the past but i wanted the best. The store i bought these from allowed me to listen to all the headphones to make comparisons. I tried all the senheisers , koss etc but after a long test the akg's stood out alot. I had never heard of this brand before then but after listening to these i had to buy them. It has the perfect balance of treble, midrange and bass with no sign of distortion at mind blowing sound levels. I am abit of an audio quality freek and never listen to things like mp3's because i only want to listen to the best. I have kef and boston speakers at home teamed up with a marantz amp, that setup cost me over $5000 australian dollars and i have to say that these headphones sound just as good ( if not better ) and all for a couple hundred dollars. However these headphones need to be teamed up with a good amp, however im listening to some music on my laptop as i type and they still sound good but not loud enough through the laptop. The headphones can be a little tight if you have a big head, but after frequent use they loosen up. If they feel tight its best to place them on something like a ball or something that keeps them open when not in use. this loosens them up and after a while they should fit your big head like mine. If you have a small head then these will be perfect. They are very comfortable and very easy to put on and off. The band adjusts perfectly to the head when you put them on, some other headphones require manual adjusting . Since buying these i have noticed on tv and movies how many recording artists use these headphones. Seriously you cant go wrong with these headphones. If you want the best then get these. They sound awesome for dance and rnb and im sure they'l sound great with anything playin through them. If you want something that doesnt sound as good and is overated then go for the senheisers.

Overall:
id keep these headphones till they stopped working, then id buy the latest similar headphones akg has to offer at the time.