We boondocked - in all senses of the word - all over Mexico over a three month period - probably for nearly a third of the total number of nights.
Can't get much better than San Carlos - either east of the town on the dunes near the condo complex, or through the town to the west. The alternative is stuck in a fairly ordinary RV park in town.
We stopped in small villages and asked the old men who were always sitting around talking where we could stop the night. We had police patrols stopping to make sure we were OK and they said they would cruise past during the night.
Camped in the forest off the road (on the road up to Durango for instance) and on the side of back roads. Had landowners telling their guards to include us in their patrol.
Also the occasional Permex of course and lots of campgrounds as well.
NEVER felt uncomfortable or in the slightest danger.
(and we speak no Spanish)
Got back north of the border with a sigh of regret that it was over -- and not a single bullet hole in us or the motorhome.