I'm in, as I had RS and now own Fox and I'm 62kg.
Back story:
I originally bought RS Sid Ultimate for my bike. It works. No bushing issue but there is an issue when I try to service mine. RS overtight the damper side shaft from the factory. The crush washer deform way too much and it's super hard to drop the lower leg out. And the thread on that side is damaged once I finally got it out. Sram denied that it's not warranty issue and charge me $170 to fix it which make me not wanting to use RS anymore and bought 2022 34 SC. Regardless, I'm not going to bias against it while describing how it feels.
How it feel:
0) I feel like RS has low compression damping. The bottom out resist almost entirely come from spring side, which is very progressive. Fox has opposite problem, HSC set too high on Fit4 and thus I don't need much spring progression on the spring side. In a nutshell, if you prefer spring dominant system with compression damping set to all the way open then bias toward RS. If you like the mix of compression damping and spring working together then Fox.
1) my RS has a bit tighter bushing. The small bump compliance is better on Fox.
2) Drop compliance is also better on Fox. RS without any volume spacer is more progressive than Fox with 1 volume spacer (stock setting on 34 SC). I struggle to use more than 85% of travel on RS. On flat-ish XC course, set sag at 20% you might end up using 70% of the available travel on RS. While you can run Fox with 0 volume spacer and use 85% travel on the same course. For me, optimal spring rate set using Shockwiz result in RS sag 24%, and Fox sag 20%.
3) However, Fox is harsher on repeated medium size bumps. That Fit4 is better than years before. But HSC is still preloaded heavily for stiff lockout mode and there is no way to reduce it for lighter rider.
This is likely non permanent issue though. Unlike that dinky Race day charger damper on RS that no one is going to modify. There were plenty of mod for earlier versions of Fit4. So, it's just the matter of time until someone offer to revalve or do more extensive mod to Fit4 to make it suite light rider better.
Also, Since HSC is set high, as a light rider, I can drop the spring progression rate down (remove volume spacer) and it's still not easy to bottom out. I suggest this route over the stock 1 volume spacer unless you bottom out 0 spacer on 34SC 2022.
4) If you are on budget. 34 SC Performance with grip damper can actually be a better option than the 34 SC Factory with Fit4 damper. Grip is more plush than Fit4 with slight weight penalty.
By any chance you consider Manitou R7 Pro instead of these 2?
https://www.mtbr.com/threads/2020-manit ... t-15359250