I use them both for different reasons and would love to figure out better ways to use both for the same project.
I especially like conceptualizing with SketchUp, then going back and forth between the two programs. I bought a one year license for Enscape and love fine tuning the design with a live ray tracing rendering - very quick and helpful.
I barely know of Chief Architect, and little about it, but glad to hear comments from anyone who has used it. I feel like CA, ArchiCAD, Revit, and probably even Vectorworks are all specific implementations of BIM, and if you don’t like how one has done it, your choice is to choose one of the others. By comparison, SketchUp is just a general 3D modeler, and several plugin developers have created BIM plugins for it like Medeek BIM or PlusSpec. If you don’t like one, you can stay in SketchUp and choose another plugin, or figure your own way through it all with native tools. I personally don’t use SU alone, I use it with PowerCADD (2D drafting) so, go for it, tell us how you like to use the two together, and why.