Travelers who plan to do some shopping along the way may find it more difficult to fit extra items into hard shell luggage. Although many hard cases, especially those made from polycarbonate, are expandable, soft luggage can still stretch more around the edges. Soft luggage set is also easier to manipulate into small spaces, such as overhead bins or luggage racks on buses, whereas hard cases really compete with other bags. http://www.altabag.com/soft-luggage-set/