I am sure class D can sound great and it would be great to try, with my sensitive Dream Maker speakers (16 ohms, efficiency: 92 dB/1 watt, Voltage sensitivity: 89 dB/2.83 volts). If class D can lift these even further I am all ears.
I want to correct an impression I may have given in my post above. I have not heard many class D amps in my audio circle. Mostly, solid-state amps at a lower price level than my MA-1s. So - I really don't know.
One thing I do know, is that running the passive speaker in an active speaker combo from an MA-1 amp instead of the active speaker amp, can result in a big lift of performance. This includes Audioengine and Elac active speakers. They sound much better.