BFF – 6

One of the best reasons to have a style six as your best friend is that the high side of style six is loyalty. Not only will they remain loyal through thick and thin, they are so relationship conscious they will probably remember your birthday (even without Facebook). Sixes will spend time and energy keeping your friendship vital.
Full disclosure: when I suspect a client is a Six, I ask if they know the birthdays of everyone in their immediate family. Sixes almost always know all of them.