Subjectively, pretty much people who own Paradigm speakers will prefer the Paradigm and those who own RBH will prefer the RBH. It's the same with just about any speaker.
Objective, it seems to me that Paradigm speakers used to be more "accurate" in terms of on-axis speaker measurements (+/-3dB or less).
But it seems the new Paradigm speakers are less accurate in this regard. The 95F is +/- 5dB from 200Hz to 10kHz.
This was what John Atkinson wrote in Stereophile:
"I'm puzzled, therefore, by the
departure of both samples
from what I regard as an
optimal target
response."
https://www.stereophile.com/content/paradigm-prestige-95f-loudspeaker-measurements
The high-end Paradigm Persona 3F looks about +/-4dB on-axis. Again, we expect +/-3dB or less from high-end expensive speakers.
https://www.soundandvision.com/content/paradigm-persona-3f-speaker-system-review-test-bench
We don't have measurements of the RBH SV-6500/R yet. This tower replaced the SX-6300/R towers, which had a response of +/-3dB.
https://www.audioholics.com/tower-speaker-reviews/sx-6300-r-speaker-review/sx-6300-r-measurements
So you have to weigh several factors:
1. Salient point is which one YOU like better if you've actually heard them, not from other people.
2. Which one has better measurements.
3. Which one has the best price.
Also check out the RBH Owner's Thread.
https://forums.audioholics.com/forums/threads/rbh-sound-owners-thread.91330/