We will be in the Cancun area for 8 days. We are planning on breaking us our trip and staying in two spots. We want to be able to dive with a company and also have access to snorkeling which we would prefer to do on our own. Which area or island should we stay at for the diving / snorkeling part of our trip? We are fine with isla, Cozumel and as far south as Tulum. We are both certified divers. Thanks!