Just saw these pics myself. Although the lines look nice an crisp, the bevel that happenes with etching will prove to be a problem for the final proto.
When sanding down beveled shapes, the surface changes thus making the engravings look different. Also, the depth of the etching can't be controlled as you can see, thin lines are less deeply etched than wide areas.
What i want to do is see if laserengraved acrylic will look better, because that method 'etches' straight down without the bevel and a more uniform depth