You'll hear a wide range of experiences, but I think it's pretty intense. Rock N Roller coaster is the first time I've been on a LIM launched coaster, and the feeling of acceleration is sudden and thrilling and an adrenaline rush. The feeling only lasts a few seconds for me, but it's enough that going into the inversion doesn't even feel so intense afterwards.
As far as which is subjectively "worse," I'd say it's slightly "worse" than going backwards on EE the first time. But for many people, that feeling of "worse" eventually turns into a feeling of "awesome" which keeps them seeking out more and more thrill rides. After riding RNRC, I decided it was my favorite Disney coaster, until I rode EE, which is now firmly planted as my favorite.
I don't know that there's any way to avoid or lessen that feeling, except to embrace it and lean into it mentally. Put on a mindset that you're craving and gearing up for speed and want to go faster. For traditional rollercoasters with long trains, usually sitting in the back makes it a more thrilling ride and sitting in the front makes it tamer. It honestly doesn't matter as much on RNRC, because of the launch.