We found Casa O's to be the best restaurant on the island. It is away from town of the bay side of the island. The best time to dine is at least 30 minutes before sun down. You can sip drinks and eat on the outdoor terrace and watch the sun sink into the bay. As twilight falls, the lights shine from Cancun and the stars illuminate above you.
Food is Mexican Nouvelle Cusine. Best steak on the island, the lobster bisque and cerviche were excellent. Service was excellent. You won't feel rushed here! Key lime pie is homemade and to die for. This place comes highly recommended from the locals.