These are two distinct types of bags made of different materials and designed for various tasks. Soft cases are most often made of nylon. They are intended for light-use and protect the tool well from dust, moisture, and minor damage. They are also more affordable, inexpensive, lightweight, and comfortable to carry. Hard-shell cases are more reliable; you can even use them to transport drums on planes. They are made of plastic and can withstand even a hard hit. However, they are quite expensive, bulky, and take up a lot of space. Choosing the right type depends on the conditions in which you store and transport your drums.