This place is the quickest at Charlotte airport, hands down! You go to any other location inside B or C terminal or even D and they not only have a ton of people in line, they are too slow.
The best thing here is customer service; they have a guy by the name of Fulton, the best customer service oriented guy I have ever seen at Starbucks or any other place for that matter. He is simply the best. In fact, now that I think about it, all the staff members at this location are nice as well, knowledgeable and fast.
Stop by and you won't regret it...right after terminal B TSA check point on the left.