Just to add my 2 cents on your choices.
Rather than either of the two horns, if I were investing that kind of money today I think I'd be looking at the JBL 4367s and putting together something right along the lines of
@dallasjustice system. with a pair of monster subs and some DRC to balance everything.
For me, here's the thing about the 4367:
If starting from scratch, why have the Son of M2 when one can have the M2 itself, plus active crossovers, for not much more?
If one already has a significant investment in electronics one wants to keep, then I get it.
Or were you thinking of with a tube amp? I was under the impression the 4367 isn't quite sensitive enough for lower wattage tubes.
Now the K-Horns would be a awesome choice if you wanted to do the AudioCheapskate route and buy used. You could put together a rig offering 90% of the SQ for 10% the cost. LOL
The K-horns and vintage reissue McIntosh combo is really just an exercise in retro-fetishism.
It almost certainly would not sound as good as the other choices (although almost certainly plays the loudest), but it certainly looks the coolest and might be the most fun.
Playing with REW and digital PEQs is cool, but there reaches a point where you're basically done, whereas the insanity of tube rolling never stops.
Plus I feel like I don't want to end my life as an audio enthusiast never having owned either a Klipsch or McIntosh product....seems like a bucket list thing.
The Dynaudio choice kind of throws me a curve, a very apples / oranges soundprint than any of the horns?
It is, but in my case, it's one I'm familiar with, since Dynaudio studio monitors (along with JBL) are amongst the ones I use in my home office hobby mixing room.
Plus, personal experience aside, they're solidly over-engineered and the wireless Connect system makes for interesting whole house possibilities.