Some extremely fast riders here have commented on their feedback with both bikes, so I feel my opinion is little bit more personal preference and single sided since I haven't tried the RR-R.
So far I've done 8 track days on my 24 V4R, which replaced my 23 V4S. Before that 21 R1, 20 S1000RR. Also done 2 days on the 24 S1000RR at Most (Czech Republic). I installed the Termignoni Wsbk style exhaust, and flashed my ECU with the T800 device included with the exhaust purchase ($3500). The exhaust made a huge difference with the T800, since the bike comes with a heavily restricted map from factory, especially the US version. I also did Z04 Brembo pads. My only plan to upgrade bike is just changing the master cylinder, which I had on my V4S. ($695)
I always believed the R was a gimmick replica for Ducati to charge extra, especially comparing spec sheets with V4S or other bikes.
Then one day, I was at the dealership for something else, and saw the V4R and decided to sit on it. The second I shook the bike underneath me, I felt a huge weight difference. On spec sheet, the V4S and V4R have only 5 lbs difference, but in real life it feels completely different. A collector purchased it, sold it back to the dealership with 100 miles on it. I ended up getting a crazy deal on it and pulled the trigger. Once I did the break-in and put the exhaust, it turned into a beast. But a different kind of beast, because of the powerband and advanced electronics. The V4R is so easy to ride fast. In corners or transitions, the power is very gentle unlike the V4S that wants to beat you up the second you twist the throttle. For those car folks, it's like having a smooth NA engine vs crazy turbo engine. For me, the V4R always feels confidence inspiring, the DTC and rest of the slide controls doing a predictable job. For me, the closest competitor I've tried has been the 24 S1000RR, a bike I quickly felt home and I was able to push to a decent pace even though it was a rental. The BMW is a fast machine, and I think the performance / value $$$ is impossible to beat. It's not sexy like a Ducati, it doesn't sound as good and build quality doesn't feel exotic. Also the S1000RR electronics feel less sophisticated, too much or early throttle can result in high side . It does the job though, just without the soul.
I am an A group rider, but I have very little racing experience. Like I mentioned in the beginning, my talent is not as good as some faster riders that have previously commented. They might be getting something out of the Honda or another brand with custom settings etc., I put it on DTC 3 and ride it all day at the track. I prefer the simplicity over the complicated adjustability.
I'm kind of done trying these other brand adventures. The 2025 V4S looks interesting with e-cbs, and even more advanced electronics. I'm curious to try that and the 2026 V4R.