I purchased a new firm mattress but it hurt to lay on my side. I needed spine support for a back problem but I needed some softness on top of the mattress so it didn't hurt my shoulders and hips.  This mattress topper definitely improved the comfort level of the mattress.  My only complaint is that it tends to sink after laying on it for awhile. I rearrange it and fluff it up when I change the sheets.  It was not very expensive so all in all I think it was a good value.