Just my personal experience with a good digital amp:
I owned, for awhile, a Bel Canto EVO 200.2. It was an absolutely wonderful amp for the money, with firm bass control and an amazing degree of refinement versus the Musical Fidelity Amp I had before it (a bottom of the line MF piece, the A3.2 CR). The Bel Canto was easy on the power bill and ran incredibly cool. It also was very well built and kept a very low profile in my rack.
I decided to sell the Bel Canto and go in an entirely different direction. I bought a Pass Labs X-250.
Lots of heat, chews through electricity like a fiend, weighs 100 lbs, and fills a huge portion of my Particular Basis rack. The Pass however, has proven to be the best audio purchase I've ever made, and was a major improvement over the Bel Canto in every area EXCEPT energy efficiency.
In all fairness the Pass costs multiples of the Evo's cost, and in retrospect the Bel Canto Evo 200.2 still conjures up warm listening memories. It showed my ears that digital amps can sound very good.