While cost isn't a major concern, I also don't want to waste money knowing my only source will be MOG, which streams at 320k, on a Macbook Pro. I have no interest in having a debate about the quality of the source or a compressed vs lossless battle. This is simply a result of a specific need in a specific environment.
My initial thought was to go with something like a Denon D2000 or Sennheiser IE60. I'm open to any style (in-, on- or over-ear, open or closed), but must keep in mind that the source will never exceed 320k (well, actually, I may have a slight preference for closed, but could easily be convinced to go with open). I've used Sennheiser HD800 and Beyerdynamic T1 through a Woo WA5-LE in another lifetime, but only because my sources were VPI turntables and Ayre CD players. I'm assuming anything remotely approaching that kind of setup is overkill to listen exclusively to MOG. I do, however, wish to use a DAC and head amp of some sort. Again, given the source, I was initially thinking of going the Dragonfly route, but as with the headphone, I'm open.