Perhaps the biggest limitation is when you try to map along the autopistas,
especially the newer ones. For instance, you can't map a trip from Tampico
to Veracruz using the autopista from south of Tuxpan, then bypassing Poxa
Rica/Papantla (180D, I think). Of course, this is a common problem for all
Mexico maps; the latest Guia Roji atlas doesn't show some autopistas that
have been done for years (Ojinaga to Aldama, for instance)."