Mine may not be appreciated by many but let me begin with the disclaimer that this is my overlall assessment and thus this is my general experience... in other words I'm not trying to be insulting and there are always exceptions to everything...
So here goes: If your current system DOES include / or matches the description of ANY of the following components then you will very likely find a transition to Class D (If that's what you'd like to do) to be sonically painless and relatively satisfying to integrate.
* More than 2 speakers
* Any "Processor" of any kind including but not limited to DSP that effects anything more than a dedicated woofer amp which must be completely separated from the main signal channels and effects ONLY those frequencies under 200hz or so [but preferably no higher than 40-50hz maximum].
* Stock power cables
* "Radio Shack - Equivalent" speaker cables
* Multi channel receivers used as the 2 channel amplification.
* Any form of [video/TV] viewing screen located between the [only 2] main speakers unless completely retractable into an essentially out-of-sight mechanism
and thus completely inconsequential to room acoustics.
* Extraneous/superfluous furniture inhabiting the room forward of the listening chair (and preferably minimized in the room in general).
* Excessive reflective surfaces including windows/ sliding glass doors... and /or excessively overdamped room: heavy pile carpet, thick drapes, etc.
* Wall outlets/ circuits which must share the same lines as major household high current demanding devices such as refrigerators, HVAC systems, etc.
I could go on. These are just general guidelines.
On the other hand: If you tend to emphasize simple/ straightforward/ "uncorrupted" and dedicated signal paths..,If you savor seriously well designed relatively minimalistic equipment with a generally sole purpose.. if it's well designed solid state or [my prefence]: vacuum tube based...If you've experimented with a number of different cables..and if you may have taken more hours than you care to admit with exacting set-up procedures dominated mostly just by listening... There's a very likely chance you will actually hear what the Class D amp is doing.
Then you'll be more likely to decipher its influence and judge more deservedly.
Personally I have yet to hear one I like but your mileage may vary of course. Good luck and happy lissn'n.