I got mine a few days ago (a day early even!) and I'm quite happy with my purchase! The sound quality is a real step up from my favorite ipod (2nd gen Nano), and it's powerful enough to drive my HD800 (not by much, but it gets the job done). I'm especially thrilled by the dynamic range it displays, I've never heard some tracks this way, and I love it.
I haven't had anything to complain about using the UI--a few nits to pick ("+" scrolls *down*???) but nothing major. Being forewarned about its nuances helped define my expectations, I simply don't ask it do do things like shuffle more than one folder, etc.
Though I wouldn't complain about a usable "bass boost" eq setting. I think "Rock" sounds slightly better than "Normal" but all the other options are useless crap.
Useless for you, godsend for others. Everyone has a different taste and the real goal of different EQs is to match as many preferences as possible. Rock preset matches your preference, that's good. Others don't, which is also good, because they match someone else's preference who doesn't like the rock preset.
I haven't had anything to complain about using the UI--a few nits to pick ("+" scrolls *down*???) but nothing major. Being forewarned about its nuances helped define my expectations, I simply don't ask it do do things like shuffle more than one folder, etc.