I have the wall mounted ones, and I love them. I actually have three and have all the thread divided into uses for the threads.
My Grandma has the ultimate wall thread holder my Grandpa made for her. Basically he took a small ladder (like you find at the second hand stores once used on bunk beds) and added dowl rods between the slats. I think he even added a middle board so she'd have extra row. The dowls are thin enough she even stores her extra bobbins on it.