It really depends on what type of sound signature you prefer in headphones imo. While I haven't listened the hfi-580 that you briefly mentioned, I have owned the denon d1000, d2000, and ultrasone hfi-780. All of which were driven by either 2move or icon mobile. (see my profile for the equipment I previously owned)
I enjoyed the d1000 for its comfort, and somewhat warm sound signature. It had a pretty decent bass output and the highs never fatigued my ears. It was a headphone that I could listen to continuously for hours upon hours. However, as much as I enjoyed the comfort of the headphones, I eventually felt the need to upgrade because I was wanting more for my listening experience...but I didn't know what it was that I was seeking.
I decided to go up Denon lineup and upgrade to the d2000. It was also equally as comfortable as the d1000 and had a slightly less warm sound signature -- though I still felt it was nearly sennheiser-like in terms of warmness. I found the d2000 to be an upgrade over the d1000 in just about every facet of sound. The treble extended higher and was very crisp and presented just right imo. It worked very well with the bass that could extend incredibly low in comparison to any headphones I had previously owned. The mids were great, albeit slightly recessed in my ears. Overall, I'd have to say I completely agree with Katun's opinion of the d2000 in his review of the d2000 found below.
http://www.head-fi.org/forum/thread/531496/d2000-vs-hd650-comparison-review
Though I loved the d2000 when I had them, I often found myself listening to my westone 3 more often. I finally realized what I wanted was a headphone that would be more forward and exciting to my ears. A headphone that would have more forward mids and bass that left more of an impact when it hit. After a 1.5 year hiatus from head-fi in which I sold off all of my equipment sans my westone 3 and sporta pro, I was given the perfect early Christmas gift of a pair of hfi-780.
I can't tell you whether the hfi-780 will be as a big of an upgrade for you over the d1000 as it was for me because we may have different sonic preferences, but I can give you my impressions of the cans. There is a huge thread about the 780's which can be found through a quick search here. As much as I love these headphones, I can definitely see how they could be a "love it or hate it" type of headphone in terms of sound signature and comfort.
First off, the comfort of the hfi-780 is nowhere near the level of the comfort that denon headphones have. While I haven't experienced any clam pressure that most users complain about, I have found that the headband becomes pretty uncomfortable after awhile. It's just too narrow and hard to distribute pressure evenly over my head. So as a result, I feel a pretty concentrated pressure going along the top of my head. Now on to sound. As I said, what I wanted most out of my headphones was an exciting sound signature, and boy do the hfi-780's deliver. The highs and mids are much more forward than the denon series of headphones I previously owned. When listening to rock with these headphones, it really feels like you are on the stage with the band as they play. The denons would put me in the first few rows of the crowd. The highs and lows are the most noted things about these headphones imo. The highs are very bright in comparison to the d1000. Many feel that they are overly bright and sibilant -- though I haven't experienced much sibilance in mine. The bass delivers the impact that I've yearned for. Though I feel the d2000's bass can extend further, it doesn't give me that initial hard hit as well as the hfi-780 do. The hfi-780's are also very detailed headphones and reveal a lot of artifacts in some of the lower quality mp3 files I have. I have also been able to hear some things in songs that I had never previously heard before on my other cans. I haven't paid attention to S-logic and can't really offer an opinion on whether it is just a gimmick or not. I can say that in comparison to the d2000 I previously owned, the d2000 had a wider sound stage. It's been a bit too long for me to remember how the sound stage was on the d1000.
Overall, I'd say if you really enjoyed the warmness of your d1000 and want to stay true to that sound signature, the ultrasones might not be ideal for you. They would provide quite a contrast to the d1000, but you could possibly find it too big of a contrast in sound signatures to be enjoyable. I feel if you want a more relaxing can which you can listen to for hours upon hours without ever taking a short break from them, then I'd say you should stick with the denon lineup. However, if you are willing to sacrifice comfort for a more forward and, imo, exciting sound signature, then I'd recommend the hfi-780 as your next upgrade.
