I live about a 3 hour drive from puerto penasco, and have gone there a few few times. I actually bought into the Mayan Grand. My take on the Mayan Grand in puerto penasco is, you must be willing to lower your standards from what you would expect in Cabo or Nuevo Vallarta. That isn't to say it is bad, it just isn't the same as the resorts further south in Mexico. With that said, the ability to drive there means you can literally decide you are going there around breakfast, and be in puerto penasco for an early dinner.
Something to keep in mind, in the winter it is rather cold in that part of Mexico. Furthermore, I am not sure about access to the Mayan Grand pools if you are staying in the Mayan Palace. The key difference, as of when I went, Mayan Grand pools were heated, Mayan Palace were not. Needless to say, the first time I went was in December, and no one was using the Mayan Palace pool, and at that time they were not letting Mayan Palace members use the Mayan Grand pools. As of this moment that should not be any issue because it is the hot time of the year, but should you look to go in the winter, it is something you should look into.
Last thing, if you have not driven in mexico, I advise you take it slow when driving. I drive in mexico at least 3-4 times a month (I live on the border), so i have gotten used to it, but driving in mexico is something you don't take for granted. For example, unless I have driven the road lately, I will not drive once the sun goes down because every once in a while you will find a pothole that could blow your time. In the day they are easily spotted, at night, much more dangerous. Lastly, I never buy mexican driving insurance because I consider it a scam, additionally, many of the toll roads in mexico have insurance included with the cost of your toll. If you are going to buy insurance, that is fine . . . i just advise you research how much and specifically it covers you (do you have to pay out of pocket and seek reimbursement, etc). Last reason I never buy mexican insurance is because no one in mexico has insurance, and should you get into an accident, it will be much easier to just pay a small amount in cash.