I have the AKG K550s and I love how they've performed so far for this purpose (I listen to exactly what you listen to at work because it's non-invasive yet energetic). Great soundstage, deep bass, but not skull rattling amounts of it. I had two pairs of Ultrasones before settling on these AKGs, the HFI-580 and the DJ1 Pro. I didn't like the fit/comfort of either that much for more than an hour, I swear they both left a dent in the top of my head. The DJ1 Pros sounded the better of the two, with less muddy bass and wider soundstage. Still, the AKGs bested them both by a good amount.
I run them unamped, but I'm building an O2 amp (slowly).
The AKGs have dipped below $200 before, I bought them full price at $299 from Best Buy (no penalty on returns there is a bonus).