I don't like the commercial sauces that are very dark brown--prefer the ones that are tomatoey colored. Cider vinegar is the vinegar to use.
If you took Marmalady's sauce without the cayenne you would have sweet vinegar. The pepper sauces are just de rigeur in Eastern NC--that is what they serve with theirs.
However, when I make pulled pork, after pulling it I put some of the following on the meat prior to serving. I put SO LITTLE of this that you do not even know there is any liquid added (the meat itself is very very moist).
Mix1C cider vinegar with 1/2tsp coarse black pepper and 3 TBS brown sugar. Mix well and add SPARINGLY SPARINGLY to your pulled meat.
Serve BBQ sauce at the table for each to use what they want.
Other go withs for pulled pork are slaw (both mayo based and a red pepper, ketchup, vinegar based sauce), baked beans, and in the fall Brunswick stew. The other Carolina custom is that slaw is served ON the sandwich.