I've had a NAD C 390DD for a couple months now driving KEF LS50s. I know these are no Cremona Ms but I'm sold on the NAD Direct Digital amps. This thing is nothing short of a revelation. The M2 is also uses Class D amplification and the C 390DD benefits from the trickle down technology as well as a few improvements. I'm honestly amazed more these two amps are not more popular. I'm certainly a convert.