I bought this pillow because I suffer from neck issues that cause my arms to go numb from shoulders all the way down to finger tips.  I am a side sleeper.  Since buying this pillow I now sleep on my back and do not wake up in the morning with numbness.  The only thing that gets some getting use to is the lower/hole in the middle.  Sometimes it is not as comfortable as I would like it to be, but I am still adjusting.