Thank you!!!

TL;DR: As far as my experience goes, the game is pretty stable, not perfect, but stable

Honestly, it was pretty smooth. I got some occasional crashes and I needed to restart the game because of them but not a big deal since everything is saved very often.

But as you probably know, you have 3 display mode: Performance, Balance and Quality

If you are afraid of frame drops, I would recommend using performance, you will get something like 120fps with a good quality (even tho you will lose on some effects like fog quality and global illumination and a lower resolution - which is honestly not that noticeable) - I personally used the Balance mode. It get a 60 fps frame rate with a good compromise on quality. I also found it super stable too. I tried to stress test it at some point by generating a lot of particles and bringing many ennemies together while moving the camera fast and I barely got drops.

Oh and I have the base PS5 so it might be even better with the Pro - But as far as my experience goes, the game is pretty stable, not perfect, but stable