Tangram & El Tio - Please add a seat at the table for me. As some may recall, I was considering upgrading the M3's to the X4's thinking I might enhance the musical experience. But upon replacing my Psvane 845 monos with the Class D MiniGans (GanFets) I have wholeheartedly abandoned any plan to upgrade. The M3's sing like never before. I hadn't heard such clarity, detail, and/or resolution from the M3's prior to the amp change-out. I find the peerless unit to be, well, if not peerless, at least so facile that I now have no desire to "upgrade." Regarding issues related to amp output/wattage/current all I can say is that the substantially increased "power" (going from 845's to GanFets) brought the M3 woofers to life - WOKE them from their slumber in relative terms. There may be something to the claim that Clayton's change to the M200 tweeter (Beyma) was instigated by supply chain issues rather than a deliberate design motivation. Regardless, Daryl Zero writing in this circle called it - if it sounds good maybe just leave it alone. Take yes for an answer. End-game speaker? Probably.