I’m developing PBR materials. For the time being just for the models, but I’ll extend that to the map rendering as well.
In order to upgrade models to PBR you just need to create a metal layer in the blue channel of the specular texture. See USP51DMustang model, and more specifically the texture unittextures/USP51DMustangReflection.dds
You can see some examples of PBR materials here (with the associated textures):