Hi Marco, the biggest new things for v5 are - improved fillets using the ACIS library, Groups, SVG format, UI theme editor with dark mode, and native arm64 build for Apple Silicon.

re:
> And, last but not least, are there any current advantages to using the V5 beta compared to the official V4?
> (I mean modelling speed, stability, better performance with Apple Silicon, etc...)

Well, the current v5 beta has all the above stuff in it which isn't in v4.

There is a collection of all the v5 beta release notes here:
https://moi3d.com/wiki/V5Beta

- Michael