I opened it up, excited to finally have this darn thing. I waited 24 hours for it to hopefully puff up. I specifically got the 5” one because I have broad shoulders. After 4 days, it measures 2.4-2.5” (and about 1” in the middle). When I put my head on it, I compress it completely to the mattress. The cooling pillow case is baggy, like it’s only 1/2 full. I’m currently using my 8$ pillow from Target, because otherwise this thing will kill my back.