I have been using the Beta with C#(Mono) since it's release 2 weeks ago on a VR prototype and I've found it very productive.

The rendering performance has significantly improved and there's a bunch of great new components - One new addition which was missing in 3.X is the 'Label3D' Node which enables you to render text in your environment, previously you had to project a spatial position to UI layer.

It's awesome to see Godot 4 come together.