So my bonus question has been asked in the general R Meta series thread but was never answered to any satisfaction:
https://www.audiosciencereview.com/.../kef-r-meta-series-release.41420/post-1481928
Apparently, the R series from 2018 (without Meta) had the same crossover points throughout.
It has been stated (I didn't find the post at this point) that the Uni-Q is the same across the series (with the exception of the R8 Meta, of course, that lacks a woofer).
Let me explain where I struggle to understand.
The R3 and R11 have 6.5 in woofers (LF units in KEF speak) and a wider baffle and hence the baffle step is lower in frequency. A crossover should be easier to design if the XO point is chosen lower. Yet the R3 has the highest LF/MF point of the lot and the R11 the lowest. The R5 and R7 with their smaller woofers and narrower baffle are just in between the extremes.
What is more, the R11 with its four large woofers can generate the highest LF output. If the Uni-Q is indeed the same across the series, one would expect that a higher XO point and / or a steeper high pass would make sense. But, again expectedly, the R11 hat the lowest XO point and what looks like a leisurely 12 dB / Oct high pass with a - 3 dB point of about 220 Hz (see post before).