This is a thread for collecting feedback and discussion regarding the current work on a new and improved shading model for the Principled BSDF node.
Just to be safe, I’ll copy-paste the note from the top there:
This is an ongoing project, and nothing is 100% certain yet. Additional components/options might be added, existing components/options might be removed and the behavior of existing options might change.
Also, Principled v2 is just a placeholder name until someone comes up with something better.
Quite a few things are still broken and/or unfinished, but some of the new functionality (e.g. sheen and the new metallic options) is already in a state where they can be used for testing.
Build bot builds of this branch can be found at : Blender Builds principled-v2 - blender.org