I did the Tennessee in the summer of 2015, but have not experienced the Cumberland yet. While voice and text were usually available from both Verizon and ATT pretty much anywhere on the Tn, data in the more rural stretches (particularly upstream of Decatur Alabama) was often one or the other, or neither. Other carriers are usually available only near metro areas. The terrain is just not ideal for line of sight. But they're always upgrading. Beautiful trip, though.