We recently bought a gel memory foam topper, with the hopes that it would ease my chronic low back pain (from an accident) and my husband's pressure point pain (from our older mattress). We had slept on similar toppers for a week or so when traveling, with great results. For the first two weeks, this one was great - we slept cool, comfortable and without any aches/pains. However after that, I started getting up with a stiff sore back every morning, and it got worse. And we noticed that there was a permanent "trough" where each of us slept. "Long term memory" foam, I guess! Although my husband was very happy not to have pressure point pains, my own back ultimately couldn't put up with the worsening sag in this topper - or its 4" thickness which was too thick to allow me to receive the support of the mattress underneath. When we removed it, we discovered several gel capsules had actually broken and were leaking through the cover. All this within only three weeks! And no warranty. We wish we could return it. The toughest part about buying any mattress product is that you don't ultimately know if it works, until after you've used it for quite awhile. It's always a gamble. Next we may try a 1" topper - hoping it will provide a little cush for the bones, but not mask the support of the mattress underneath. Wish us luck.