I have the oppertunity to try two brands of memory foam mattress. Premium Memory Foam 4-inch Mattress Topper Serta? Ultimate 4-inch Memory Foam Mattress Topper Originally purchased the "Premium Memory Foam 4-inch Mattress Topper" and love the Gel-like matteress and decided to try the Serta for my other bed. I was a bit dissapointed by the foam. I felt more like laying on soft bread and it did not help with my back. I really prefer the Premium matress that feels more like soft clay. So you need to decide what feel you are more geared for before getting the foam. They are different!