My boyfriend is Puerto Rican, but he comes to Kansas City each December.  As you might expect, he does not need warm footwear in PR, so in KC, his feet get cold.  I originally got the higher boot, but they were too tight.  Plus, he liked the lower cut boot's look better.  I bought these a little bigger than his normal shoes.  Granted, he has thick ankles and calves, but the larger size fit him perfectly.  He now has toasty feet when he visits and is a very happy camper.  I love Uggs!!!