vlach
1000+ Head-Fier
My Nuforce HDP is no slouch and I still think it is one of the best values in this hobby, but it is outclassed by the M8 and will be put up for sale once I re-case it.
I owned the Icon HDP for a while and thought it was a pretty good headphone amp, however I found the built in DAC to be very average. Are you comparing both units as a whole (DAC+amp), or the individual sections? I would be interested in your evaluation comparing amp-to-amp fed from a common DAC...