The last time I was there (and this has been a few years) the beach wasn't much to write home about. Daupin Island is right on some major shipping lanes, so you get a lot of algae, jelly fish, and the like churned and washed up. But other than that, the Alabama-Mississippi coast is pretty nice as I recall. The drive into Mobile isn't bad at all, if you want to do something urban. If you want a really great beach down there, I recommend Ship Island, off Biloxi. You can't sleep on the island, though---you have to take a ferry on and off in the same day.
