I owned a Belcanto s300 amp. back in 2007. Used it for 3-4 years with various speakers including my current Harbeth Shl5 - mainly in my second system. For me, subjectively, I never liked this amplifier. Now I have a Belles Soloist 5 amp - which is a class A/B design. IMO this sounds significantly better. I felt the belcanto sound to be clinical and overtly analytical whereas the soloist sounds more musical and warmish - notwithstanding the s300's power almost 3 times that of the soloist into 4 ohms. Not heard any of the newer belcanto's or any other designs, perhaps they have improved. I really like the convenience of Class D, small, cool running etc, and am really looking forward to a design I can be happy with sonically.
Cheers,
Sid