They're pretty similar in terms of size and being more private practice-oriented university programs (there are, of course, plenty of research opportunities at both but it's not an emphasis at either). Both have good reputations, though I would put UNC a little higher on my subjective top whatever list. I did feel like the MUSC residents were very happy overall while the UNC residents seemed a little less happy and a bit more overworked. Just my impression of things. You can't go wrong with either, though!