As per my post above, I preferred the Pass XA200.5’s driven by ARC Ref 5 SE to VX R Twenty with KX R Twenty. I found the Pass had a fuller, more musical sound and the Ayre comparatively leaner, perhaps owing to the bass coherence you cite.
I am pretty happy with the X350.8 but as you know in this crazy hobby, you always wonder about the ones you didn’t get....
My speakers are the Vienna Acoustics Kiss which in spite of a low impedance dip, is an easier load than the Rockports, so the strain at high volumes is not as apparent sonically even though I do see the meter twitch and leave Class A.
I do enjoy the speed and slam the X350.8 gives (someone else had a very apt descriptor of "ballsy") which I have been told is a characteristic of Pass Class AB vs Pass Class A amps. I am unsure if this is true as I have not AB’ed them in the same system but do remember the XA 100.5 being very musical if a bit too laid back with some older Sonus Faber speakers.
Thanks again