Thanks papa, but is "heads up" enough? I'd like them to have their heads "on" when they get home.

I am going to direct these guys to this Board to read the responses, positive or negative. They're not listening to anyone and part of me thinks that maybe the trip could be done more safely if they had more knowledge. It's the Mexico leg of the journey that worries me the most. Bad things happen everywhere though, but the crimes are so brutal up in Mexico. If they stick to the well-traveled/touristy roads in Mexico, is that safer?