I started my journey with my first decent pair of Koss PortaPros, moving up to the Denon D2000s, the Beyer Dynamic DT990s, Ultrasone Pro 900s, still not being satisfied with those previous head sets I finally took the plunge and found  great deal on the Denon D7000s. Truly the best headphones I have heard to date, even after owning the Beyer Dynamic T1 and HifiMan HE500, I still prefer my D7000s as my go-to headphone.
 
For those who have heard the D2000s, 7000s differ from the 2000s with much richer sound, by that I mean a better interaction between bass, treble, and mids.. all while increasing soundstage and clarity.. I can definitely tell the difference in sound between the two, not to say the 2000s sound bad, they sound great, but the 7000s are priced high because they are the best in the lineup (aside from looking awesome). Something I noticed with the 2000s was presence of some sibilance, the 7000s are better, not perfect, but a warm amp will correct the sibilance.
 
I can't recommend this to everyone, its a premium price to pay for a headphone, but the way I look at it, if you are the type of person who enjoys headphones, you need a pair for daily use (something that can handle being beat up a bit) and you need a pair for winding down at home and relaxing to some of your favorite music.. for that the Denon D7000s are perfect; super comfortable and light with excellent audio quality.
 
Here's a little story for some of you disbelievers.. My DJ friend never liked Denons, *because he thought their DJ equipment was poor* never gave Denon headphones one look (he was always a Pioneer/AKG man), I let him demo my D7000s for 5 minutes and he got the biggest grin on his face, it was really funny, he just couldn't believe how great they sounded and now he's craving a pair . 
 
Conclusion, if you have money to spend on a great headphone and already have a good amp/dac these will be perfect for you, I listen to a lot of electronic, house, pop and some rock/jazz these do everything well, you can't go wrong..
 
 
 
 

I owned the XB 500, 700, and the 1000s. I currently own Denon D7000 and Ultrasone Pro 2900 (so I may compare).. The XB 500 and 700 didn't give me any benefit to my current setup, they sounded muffled, the bass was present but not very clean, they didn't suit my taste. I read a great deal about the 1000s so I took the plunge once they became available in the US. I was really excited to get them cause I thought the ultra huge pad look would be kinda cool and comfortable.. But after wearing them for about an hour I have to say, I'm not crazy about having those massive pads on my head, almost feels claustrophobic, not because they are closed phones, but because they are huge and you really sense it when its on your head.
 
As far as sound quality the 1000s definitely sound much much better than the lower lineup. They don't have loud thumping bass that the 500s had, but they have this weird ability to create almost a suction type feeling on your ear drums when sub bass hits, it was actually so weird I had to take them off the first time I heard it. They are neat in that respect (hopefully thats safe for your ears-long term), but their audio quality doesn't come very close to my other headphones and it didn't give me enough of something different (sound wise) to merit keeping them. So I did return them after a trial period and personally for the price I would recommend other headphones with similar costs (and there are many like the Ultrasone Pro series, the Sen HD650s - Amazon sells them for $360 often - even the Denon D2000s sound better - another pair I previously owned).
 
I can't really merit a recommendation for this headphone for the price, maybe if it could be had for $200 it would be fun, but if you're looking for your first big purchase of a nice headphone, i would do some research and get a pair with better sound quality.
 
I do want to mention something, I read a few peoples reviews stating that the 1000s sound "amazing" for house and electronic music... I think they sound ok, I listen mostly to electronic music and both my Denon and Ultrasones do them much better justice than the Sonys did, especially in clarity, bass reproduction, and vocals (just my opinion).