Guava will not grow in South Carolina without protection. Even hardy citrus needs protection there. If I lived in SC I would be growing fire blight resistant pears, select Chickisaw plums, Muscadines, Rabbit Eye blueberries, Peaches, Chinese Jujube, Pecans, Paw Paw, Blackberries, Che, and maybe a satsuma (but it would definitely need protection).