I think they are very speaker dependant. My one audio bud, listened to the Bel Cantos (he loves their DAC) and he found them unsatisfying and went back to his big class a/b amps. I have a pair of Nuforce SE9s and they work wonders with the Mbl 101Es. But that's just one application. I think you must try them yourself and carefully work them into your system with cable changes, tweeks, amp stands, etc. to get the magic mojo.
Peter
Peter