I'm getting ready to pull the triger on my first bench build. I'm planning a Roubo style featured in Schwarz' book. I have had some Ash in storage for this project. I also have some Walnut available. I'm thinking of inserting a couple of pieces of Walnut in the top for contrast with the Ash. Looking at the density and hardness of the two they are not far off. This may not be the absolute correct bench. I just thought it might be interesting. Any thoughts?