As a protection for the pillow it does the job.  I found with regular linen pillowcases the case and this slide around and the pillowcase get twisted around, with flannel pillowcases that doesnt happen.   I also found if you zip the cover closed too much it traps air inside and you now have an air pillow with all the same effects of trying to sleep on an air mattress.  Overall I prefer the other protection cases I own.