As a resident of South Walton for 8 years here are my Bellsouth/AT&T experiences. When AT&T purchased Bellsouth about 3/4 years ago coverage got much better. There are some weak spots
like Grayton Beach near 30A intersection, and inside the Redbar. But Redbar has wireless access and you can get a signal on the deck and in the parking lot. But there is a strong signal on the Beach in Grayton. And the signal is good to very good on the beach in just about all of South
Walton. The only current down side to AT&T here is that we do not currently have 3G coverage. So if you get a new Iphone you will not have 3G speed here. But if you travel you can get 3G speeds in most medium to large cities in the US. Overall I have been extreamly happy with my iphone / AT&T coverage in South Walton. I have only experienced dropped calls on 331 between Paxton and Defuniak Springs. By-the-way I have found my AT&T coverage/service to be so good that I dropped my landline phone about a year ago. AT&T phones used for reference: Motorola Razr (2004-2007), Iphone (First Gen) (2007-2009). I am waiting on 3G to arrive here to upgrade to the new iphone. (iphone 3G (S).