Thanks for the thoughts everyone.
Currently I'm running the m50's with a 2-channel NAD amp (2400), and the rest of the speakers with a multi-channel NAD amp (906), and was hoping to be able to get rid of an amp to save some space.
But if the Onkyo's amps didn't sound as good as the NAD amps, then I would just keep using the NAD amps.
If budget is the main concern what you are doing makes sense. I've experimented with that receiver and it clips at not that high volumes and at loud transients. If you are planning on using it at low to moderate levels its OK.
However if you are asking are you giving up sound quality by selling the separate NAD amp and relying on the very hot amp inside the onkyo receiver box then the answer is that it would be a mistake. Do not believe the over-simplistic statements that a receiver amp is the same sonically as a capable separate amplifier. The high heat (hot to touch) along with the radiation from the amp inside the box will affect sound quality.
