I bought one of these six months ago to store guest bedding, towels, duvets and pillows. I have now bought a further two as I am so impressed with the quality of the product. I have bought other vacuum storage products before and was not at all satisfied as they would lose their vacuum within weeks, however this case lasts until the next occasional guest arrives. The expandable straps inside help to keep the items inside compact.
As another reviewer has commented, it helps to pack items in roughly the shape as the container, in order to ensure even compression and maximum use of space. I have also bought the closet storage (on a hanger) - fingers crossed that they are as good as these beauties.