I bought 2 of these to fill in my King Size Pillow Shams and the other 2 to use for sleeping.  They arent as long as I needed for the shams but I added another old pillow behind it and they worked out fine.   For sleeping they are very comfortable.  I love them, though my husband prefers a more stiff pillow so I ended up getting both!  Cant go wrong for the price. 

Pros: Price, comfortable
Cons: Not as big as needed