As PP said, the weather will be similar whether you choose Mayan or Punta Cana. Therefore, you have to decide whats important to you. Generally, Mayan is cheaper than Punta Cana. Punta Cana however is known for its beautiful beaches so if thats what you're looking for it might be worth considering over the Mayan. I was deciding between the two as well. I suggest finding a couple resorts you like in both places and reading lots of reviews. Then based on prices and exactly what you are looking for narrow it down further. Good luck and happy planning!