For me, and probably for many others here, the inuke amps are more than adequate. I have a long list of things I would like to upgrade in my home theater. "Upgrade the Inukes" is not on the list. I have a 6000dsp, a Nu4-6000, and an older EP4000.
In fact, I have a Nady 1100 watt amp and a Crown XL1000 that I used bridged for sub duty that I would like to replace with a NU6000dsp. I am using those two amps with a Minidsp but I would still like to have the 6000dsp's limiter feature as well. I have driven my SI18 sub to distortion with the Nady in Edge of Tomorrow (not sure if I was overdriving the sub or clipping the amp or both) and using the limiter in the Inuke would be a simple way of controlling that.
I am sure there are better amps, but for some things, good enough is good enough. I don't see what a more expensive amp would do for me.