I use it for every material setup but I actually use Designer more than Painter, as I’m an architect and most of the times I need seamless textures.
The big trouble with painter is that you have to have a unwrapped UV map for your model in order to use it and that is never seamlessly achieved in SketchUp.
What I usually do is that I create a custom export map for a low resolution SketchUp texture with blended alpha (if needed) and every other high res texture is exported to use in render material. That way Sketchup doesn’t bog down on complex models and renders are high res.
If you’re going to use more than one render engine I’d also advice you to export DX and OpenGL texture maps for each material you have.
In Designer that is super easy, in Painter I’m not so comfortable.
I’m using Thea though, not Vray. In Thea it’s very easy to use PBR textures but it doesn’t work directly with .sbsar files. I think vray supports those files but I don’t know if that’s available on vray for SketchUp or only on max.