I listened to the KEF LS60 in a perfectly treated room (at a shop). I also listened to the KEF LS50 Meta Wireless.
So... I gotta say that the LS60 does it all, especially deep and clear bass. But the LS50 Meta Wireless was like 80% there. The missing 20% being the bass.
To me the LS60 is just like a pair of LS50 wireless II with 2 subwoofers. And I could happily live with that.
The LS60 is about 7000€.
The LS50 wireless II is 2500€. The KEF KC62 is 1700€. So LS50 wireless + 2x KC62 = 5900€. I guess you can add another 300€ for stands. I'm scratching my head wondering why the LS60 is 7000€, not 5000€. Granted, it is a more elegant solution than having separate subs.
IMHO, you're better off getting a pair of AudioVector QR3 for 2600€ and spending 2000€ on an integrated streaming amp.