I have seen other high end heads that have that same washboard appearance in the combustion chamber. I don't quite understand it. It looks like sloppy work to me. I know ridges like those in the picture that are in close proximity to the seat and top cuts are flow killers on the flow bench. The only way I could see that being beneficial is if helps re-atomize the fuel for a more efficient burn. If those kinds of ridges help, I would think they need to be oriented in a particular direction. The orientation of the ridges in those pictures seem to me to be computer generated to follow the area that needs to be machined. Maybe someone can correct me, but I'm still leaning toward sloppy work. A Trick Flow chamber is CNC cut with a much, much smaller stepover (distance between cuts). It is a nice looking chamber.