I’m not sure about the nCore, but as for the ICEPower units, I would say that’s true, they really don't add anything to the signal so if you need warmth or liquidity added these are b. .... however....
Using my current reference speakers I could not tell a musical difference between an ICEPower 250ASP and Parasound A23. The A23 is often described as warm, and my system is as well by listeners who do not kwow what the amps are. My sources are a Mytek Brooklyn DAC feeding a Parasound P7. I could see myself trying out a tube preamp here or there to add some liquidity to the top and magic to the midrange, but the sound is most definitely not lean or soul-sucking like I have heard some mass produced processors to sound. I’m pretty happy with what I have, but tubes are tempting. :) I have heard from a couple of users who attempted to use the ICEPower amps directly from PC sources, that did not go very well for them, I'm afraid. :D
Certainly for movies I lack nothing. Engagement, dynamic range, dialog intelligibility and transparency across the audible range are excellent.
Some of this may have to do with having relatively easy to drive speakers. Min 4 Ohms, and 8-10 in the treble, where I have read at least 1 complaint of the ICEPower units with Maggies. The ribbon tweeter in Maggies becomes inductive, while my speakers use an AMT which remains resistive from the crossover frequency upwards. It may very well be that there is some speaker dependent behavior. On the other hand, the Monitor Audio speakers are fairly straightforward to drive and nCore have an even lower output impedance than the ICEPower units.
My surrounds are even easier to drive, remaining around 8 Ohms through the midbass, and min 6 elsewhere.
So, to sum it up, if you have reasonably normal speakers without reactive tweeters and your sources have all you need in terms of warmth, tone, etc. I think the current batch of Class-D amps is an excellent choice, and the NAD 7 channel nCore a fabulous bargain.