I've stayed at the Atlantic, Bal Harbour, Diplomat and several other hotels in Miami (SOBE so not Starwood). Atlantic has the best beach along with a decent pool and spa. Plus the best restaurant in Florida (owner/chef are NY expats and the food shows it in terms of quality and attention to detail). Bar is also good, in the running for best in FL, great drinks, quiet, but with an undercurrent. I was very skeptical about the Atlantic prior to staying there, but I'm sold on it being the best choice.