Safer to travel from Oaxaca to Zihua or Puerto Escondido

Another question...people with no Spanish language ability, 3 couples, in their thirties, want to travel by van from Oaxaca to Puerto Escondido. Your response has been that it's safe. In my experience, Zihua and Puerta Vallarta are much more interesting. These people don't surf, so I wondered why they chose Escondido. But I also wonder how safe it would be for them to travel to Zihua or Puerto Vallarta.. appreciate your comments. I'm the mom so they probably won't listen to me anyway, although I'd been in those situations 20 years ago. Gracias