We just got back from a week in Murphy, NC and we roamed on AT&T exclusively, coverage was very good around most of the town and we had EDGE all the time but if we went into the Nantahala National Forest the coverage was very spotty, I know some say Verizon is better in that area but the locals I talked with said US Cellular was king. I really didn't expect to have coverage deep in the forest anyways and I was happy with the service I got when we were at our cabin and in town.

We came back through N Georgia and I was surprised T-Mobile has native coverage in many rural areas, like Blue Ridge and Ellijay. Atlanta Metro has strong 3G and extended well outside the city we had 3G all the way up in Cartersville

Overall T-Mobile performed very well I had very few areas with no service at all