Some years back people were raving about the water beds and how they helped their backs. Now, there are so many brands out there. We have a temperpedic and it does retain heat but I love it as I'm always cold. We turn it every time we make the bed as it tends to mold to the body and I feel sometimes like I sleep in the same spot all the time. I believe I read we should change matresses every 10 years but we don't seem to be that rough on them as they last longer.