I like wide backs. After wrestling with a queen or king quilt to get all the borders on, I am glad I do not have to do the same seaming the back. I have found a good selection here. I prefer that to a sheet as it is hard to get sheets for a good price that are 100% cotton.
When buying wide backs, make sure they tear instead of cut the edges, same with wide muslim. Folding and rolling wide fabric on bolt distorts it and cutting will leave uneven edges. All the local stores including Joann's tears wide backs.