Material Blend Methods and Cost

I’m diving a bit deeper into Unreal and have some questions regarding material blends and cost. Between Material IDs on a mesh and mask driven definition of materials: Is there any cost advantage to one over the other? In a scenario where you have 4 Material IDs on a mesh or 4 masks packed in map, does one cost more than the other?

On that note it’s safe to assume that baked down unique textures are going to be cheaper (in material instructions but more expensive in disk space) than a material with parameters than can be spun off to make variants within the engine. Are the savings significant enough to justify say favoring unique maps made in Substance Painter in lieu of making masks and compositing the final material in engine? Is it possible to use the material instance and parameter workflow to create a masked material that can be tweaked in engine and then render it down to baked texture?

Thanks!

you can bake multiple materials into textures with the proxy geometry tool.