I quite agree that my setup is far from high end, and that a better source and amp would of course, make this comparison a little more comprehensive. Having said that, however, the things that were better on the D2000, namely comfort and soundstage, will always be better than the Pro 900, regardless of the source used. I feel confident in proclaiming that, no matter the setup, I'd probably prefer the Denons for the reasons stated in the review. More importantly, more people on this site have gear closer to mine (in terms of fidelity) than those who have $3000 dollar DACs and amps that my review, therefore, is applicable to a much greater audience.
In about a year, when I have income to upgrade my gear, a very high end DAC will be the number one upgrade on my list. After that, however, I plan on pursuing high end custom IEMs, so a future comparison with the Pro 900 isn't likely.
On a side note, I'm not sure what you meant by mentioning software. If there is a better way to listen on a Windows based PC than Foobar and its WASAPI plugin running FLAC files, please let me know.
Hate to tell you the following, but I think you really should know it:
1. Matrix M-Stage V2 Favors Denon over Ultrasone, no doublt
2. Your source really does not do justice to to Pro 900: as you said
Pro 900 is very unforgiving for having bad sound sources
and by source I mean both hardware and software
not everyone owns a CD Player and hook them to some fancy DAC
but as a past-user of both cans just have to point them out to you
maybe one day your opinion will shift again
In the mean time, thanks for the review