I currently own AKG K702 headphones (which I do enjoy), but I'm thinking about adding the 880/600 to my collection - just for a little variety. I've not heard these particular headphones, but from what I've read, it sounds like they share many of the same qualities with my AKG's. I only wish they had a removable cable as I will need about 12-15 total feet of cord. Guess I will need to invest in a headphone extension cable.
I plan to power these with a recently updated vintage H.H. Scott LK-48-B Integrated tube amp (that's the kit version of the 222D)...should be a nice match. I primarily listen to 16/44 FLAC files ripped from LPs, the set-up chain looks like this:
Toshiba Laptop + External Drive + JRiver MC -> Musical Fidelity V-Link II -> Cary Xciter DAC -> Scott LK-48-B Integrated Amp -> Headphones
The only reason MF V-Link is in the chain is I have two systems - one for normal speaker listening and one for headphone listening. The V-Link coax output runs to a Cal Audio tube DAC (for the main rig) while the toslink sends signals to the Cary Xciter (for headphone listening). This way, I can marry two systems without having to swap cables/equipment around.
I think with both the 702 and 880, I'll have two of the best bang-for-the-buck headphones in existence.