My local JBL/Harman/Revel dealer did the (DBT) shootout between M2 and Salon2: https://www.thescreeningroomav.com The results are posted on AVS in the speaker sub-forum, M2 and/or Revel threads, somewhere. IIRC the results were very close, sort of like comparing a 9.5 to a 9.6 to call a winner.
Never heard the Kii's (nor likely to) so no opinion. I will note that many of the advantages listed for the 8C's are the same things optimized in the Salon2's crossovers, baffles, and waveguides but I've no idea how much better (if any) the 8C's are or would sound to me. Preference is what it is... Having control of all those parameters would be cool but I'd spend too much time tweaking.
Never heard the Kii's (nor likely to) so no opinion. I will note that many of the advantages listed for the 8C's are the same things optimized in the Salon2's crossovers, baffles, and waveguides but I've no idea how much better (if any) the 8C's are or would sound to me. Preference is what it is... Having control of all those parameters would be cool but I'd spend too much time tweaking.