@ghdprentice 100% agree with your assessment of the M900u;
Had that amp with the C900u, on numerous occasions over the years with Dynaudio Confidence 30, Focal Sopra No2, Dynaudio Confidence 50. Bass was constipated and dry in all cases and in different rooms. Excellent detail and soundstage but my Pass Labs XA30.5 actually sounded way more engaging and enjoyable. Could have been poor speaker synergy, not sure;
Had a Pass X350.8 with the bigger Dyns and it was excellent.
I would highly recommended a Pass Labs X250.8 with Magico A3; You might also want to consider Coda; I think the Pass labs bass and midband is richer and warmer than Simaudio and have a suspicion the Moon amps will be a touch thin with the sealed magico.