My experience thus far — after two days of driving 10 hours each day — is that there is good news and bad news.
The good news is that the road — there is only one road that goes from the northern tip of the Baja peninsula to the southern tip — is in very good shape. In fact, I would say in excellent shape.
The bad news is that it is only two lanes wide except for a couple of small sections. That would not be so bad except for the fact that there are NO shoulders, no guard rails, and periodic and sporadic traffic calming bumps.
The lack of shoulders is more serious than it sounds. The reason is that there is a drop off of between one and two feet at the edge of the pavement. So, if you wander just slightly off the road you are in a world of hurt.
The bottom line on driving in Baja is that you have be unbelievably focused and attentive to what you are doing.
Oh. I forgot to mention the 18 wheelers, trucks, and buses that barrel taking every inch of their side of the road. No room for error.