Asphalt pavement for increased vehicle speed. Also includes tiles for lane marking (single and double lines) and various hazard areas. Original mod by Arcitos patched for 2.0.
I don't see any harm in adding a setting for it, I'll add a checkbox that makes it a requirement when research cost is set to normal or expensive (still requiring purple science) when I have some time. It'll be off by default so when I drop the update make sure to check the startup settings for it.