In school I always learned "woher kommst du?" I just started the FSI German course, written in the 1950s, and they use the construction "Wo kommen Sie her?" I understand that they're just splitting it and I'm sure it means the same thing, but I was wondering what kind of person would use each construction? Is it formal vs colloquial, modern vs old-fashioned? If I used "wo...her," would I sound weird, upper-class, seventy years old, Swiss, etc?