This was created from a 201 x 201 regular x/y grid of points whose z values varied at random and resulted in 80,000 triangular faces (the SKP file is 78.1MB).
Looks really convincing, sandpaper 250.
Not my favourite “tool” though I dislike anything that has to do with painting and preparations therefor.
Now render a flat face with a displacement map and compare the file sizes of the two models .
In my opinion bump will be enough for this result render time will decrease
I textured the flat face in SketchUp with a screenshot of the original render … now the file is only 1.86MB in size (mostly due to the large imported image). Of course, the original purpose of this exercise was to model the sandpaper, not render it