We ordered this memory foam mattress to put on our existing King pillow top mattress. We love it! My husband says it has made a world of difference and the cost was excellent. It was certainly a lot cheaper than replacing the whole mattress set. The only issue we have now is that the bedding doesn't fit any more. But hey, we sleep better! I ran into a lady in a store looking at the 4" memory foam mattress toppers and I suggested that she look at this one on Overstock, one because it is great and the other because the cost is better.