Because the pillows that came with my Navage often seemed awkward to insert, I thought I would try the smaller size. I didn't realize that what was smaller was the opening, not the exterior. As a result, these really didn't work as well for me, so I am back to my "mediums". However, that is no fault of the product and I am glad they offer various sizes so a person can experiment to get the best fit. The Navage is such a great invention it would be sad that anyone would struggle with less comfort than possible.