We travelled with a group and one of the rigs was a 40 foot NEWELL. The organizers had to make some special arrangements for campgrounds as generally speaking people RVing in the BAJA use smaller rigs. I think you might miss some exploring opportunities due to lack of parking opportunities.
The BAJA is a completely different Mexican experience. We have seen and enjoyed most of Mexico Including the BAJA. But BAJA has its own unique cultural feel. It doesn’t have the old world European architectural history and feel like the mainland but has its own magic to it. And a great naturalist experience. The people are fantastic, the food is great and the experience will be unforgettable. If you are up to it get some basic Spanish skills and you will have an even better cultural experience.
Consider checking out the BAJA winters website. Good people and you’ll have a more relaxed trip.
Enjoy.