Not sure if you are intimating that it is the ICE tech that is an issue (to you) or if the SMPS is not a problem to you.
I have not, and will not, use the term SMPS to refer to a power amplifier in general, since the last two initials stand for "Power Supply." To use SMPS to refer to a switching audio amplifier in total is incorrect. It negates several components entirely, and fails to acknowledge the improvements that have been made to make it wide band.
ICEpower refers to a particular brand of Class D which is owned by B&O. ICEpower 250 ASP is a specific model of amp which includes a power supply in it, and it is what I have the most amount of experience with.
To repeat my original message: The tropes about the terrible sound quality of Class D amplifiers are not supported by any of the many reasonably good Class D amplifiers out there. Nor is there any evidence that you can hear the switching noise anymore. Not for decades.
If we want to talk about the positives, and negatives, we have to stick to experience and specific models. All amplifiers have a negative. All have something they could do better or differently. Seeing 1 measurement and going "look look, Class D is terrible" is not scientific. To close the loop, you have to connect it with listening. And that’s where a lot of anti-Class D bias looses all of its wind.
Again, referring back to my original post. I like this specific model of Class D better than some linear amplifiers, but not better than the Luxman I'm listening to now.
With this specific example, and I don't think it was by any means the best available today, I never heard anything that said "Class D." So I imagine that not only are there a lot of other Class D amps that don't sound bad, but that they've made significant strides.
Best,
E