Everyone raves about Tsali, I lived in NC and ATL, Ga area for a while. My recommendation would probably lean towards hitting the North Georgia area. There's primitive camping and a really nice biking loop near Elijay, Ga if you're all about that style of camping. Also, about forty minutes NE of Elijay is Helen, Ga which is a great town with camping (primitive and not so), solid lodging, a great German styled town with fun restaurants AND great riding with a few different loop option rides and a race course all within riding distance from the town, the App. trail cuts thru there too and there's great road riding in that area also, really, really nice area. My point I guess is, with North Georgia you get a lot of different riding options all within an hour or so of one another. Personally, I'd stay in Atlanta for the nightlife, then, base day trips north. You won't have to drive more than two hours one way for a ride. There's a ton of trails that you can put twenty miles on the bike no problem. Where ever you would choose to stay, there's a ton of different riding options that are a reasonable drive from where you'd be at. There's tons of national rec. areas up there, lots of ride options, and both Helen, and the Blankets Creek trail just north of Woodstock both offer race course style trails as well, so you could do long grueling national rec areas one day, then do rolling, fast race style loops the next. Just a ton of options in that North Georgia area and most of them are pretty well documented on the internet so you can plan out your time there before you arrive and know what you're getting into. My opinion on the NC deal is that the riding areas tend to be a bit more spread out from one another, making it tough to bed down in one place. Just throwing the idea your way.