You ask a tough question. You may get a lot of opinions, but the reality is that no one else can pick a place for you to live. What some folks love, drives other folks crazy. If you browse this category, you'll find much love for MB from some, and others who can't wait to get away. IMO, all 3 states have both nice areas and not so nice areas, but that's based entirely on my preferences, which are likely to be different from yours. Two suggestions:
1) Find a job, then move there. DO NOT try it the other way. SC's unemployment rate is double that of Vermont. GA and NC are almost as bad. Unemployment in Horry County (where Conway is located) currently exceeds 13% and that number is understated. Some counties adjoining Horry exceed 20%.
2) If you really think you want to become a Southern transplant, rent for a couple years and explore all 3 states. You'll either find your perfect place or decide VT was a pretty neat place after all.
Good luck with your search.