Meanwhile, I have some class D updates and can share my first (still superficial) impressions on a class D Cherry MEGAschino amp (a demo stereo version). I got it recently from Tommy O from DAC (Digital Audio Company) together with a (demo) DAC SHV 2 with volume control.
Let me note that MEGAschino is not a typical representative of class D: it is quite heavy (about 20 kilos), not as small, it does get hot (not extremely hot) and costs a few times more than an average class D amp. So nice characteristics of a class D amp are not present in this amp, which is based on a module designed by the same company (DAC). At the same time, it gives a detailed, clear non-wax and non-frozen music reproduction. I can even say that the sound quality is more alive and detailed than that of may class AB amps, a surprise for me. Roughly, it sounds like a good solid state class A amp while gets less hot and is still less heavy. Again, these are my first impressions that might be completed or/and altered later.
At the same time, i am not impressed with DAC SHV 2 (about $1500 new). It has a single digital input. As a (passive) preamplifier, it was not so efficient with MEGA -- the sound had no dynamics. As a DAC, it is slightly better than PS Audio Gain Cell (slightly more soundstage and definition), but Gain Cell costs the same and is also a real preamplifier (with enough number of digital inputs, several line inputs, coaxial, optical, USB etc).
Currently I use $650 Nuprime HPA 9 headphone amp with MEGA as a preamplifier, with very positive results (although HPA 9 is class A). My desire to stay in class D is not (yet) fulfilled. Though in terms of ratio performance/price MEGAschino may not beat other class D amps, in absolute terms, it is a very good sounding amplifier. I hope I will stay with it in my main system.