Has anyone driven this route? We plan on going thru the Tecate border crossing (smaller, but less busy than Tijuana). - from Tecate onward, looks like it's Route 2D. Is the road hilly or flat? Do we need a 6cyl car or can we get by with a 4cyl? Alternatively, there is Route 3 which looks more hilly and goes via the Guadalupe Valley (wine country) - Toll road in Baja; do they accept US$ or only Mex$ - Can we purchase the Mex car insurance once over the border, or in USA side? TIA!