Over the years I've owned some of the finest sounding amplifiers ever made. I'm positive that a few would still be competitive today. I returned to the hobby this year after a 9 year absence - starting with a clean palette. I started to research the current SOTA in amps and preamps with absolutely NO interest in class D amplifiers. I never heard one that came close to reproducing music realistically among their other problems.
I set a budget of $8k for amplification hoping I would find a mint used set of monoblocks in that price range. I kept hearing great things about the Bel Canto 600M's and even though I was dead-set against class D, I took a trip to hear them. To my total surprise they sounded great - no hint of that sterile class D sound - no lack of musicality and detail. In fact, inner detail retrieval is outstanding. I purchased a pair.
No, they aren't perfect, but if you write off class D amplifiers based on the examples of 5 years ago, you would be making a mistake. I have a very musical, detailed presentation with good slam and attack. There are other positives. The cost compared to my budget was far less and a bargain for performance at this level. I'm also happy that they run cool. My previous monoblocks - Sierra Audio Denali - required me to run the A/C in the winter in order to keep the listening room comfortable.
I know there are other great options at the budget I set. I listened to many before making my decision. It came down to buying a great set of amps for only $3k (dealer demos) that compete with much higher priced amps.
Class D has come a long way.