I really like the new look and not had any major issues so far: The only app that's not working is Vanilla and control centre has let me remove a lot of icons from the menu bar so it's not a major issue
All my major 3rd party apps (Visual Studio for Mac, VS Code, IntelliJ Idea, Fusion 360, VMWare Fusion, Simplify 3D, Office 365 and Adobe Creative Suite) are working fine
I've only upgraded my MacBook Pro so far (I needed to check out app compatibility before hitting my main machine), but will be tackling the upgrade on my Mac Pro over the weekend