We currently own a sleep number bed and could not find a comfortable adjustment for it. We went to the sleep number store and the rep wanted to sell us a $***+ 2.5" memory foam topper. We gracefully left the store and found this one. We figured why not give it a try, half the cost and almost twice the thickness. It was great. My wife who likes a really soft mattress was very happy, and I who likes a firmer but comfortable mattress was happy. It made our expensive uncomfortable mattress VERY comfortable. So much so that I softened my side and my wife firmed hers up a little and now we dont have such a big difference in mattress heights. As far as getting hot and the pad not breathing we had no problems at all. It was very comfortable temperature wise. Two notes to mention. Many people said that the mattress had a chemical smell and walked down the mattress. We had no smell at all, and I mean at all. We pulled it out of the package and let it sit for the rest of the day (6 hours) and then made the bed and went to sleep. They do say to leave it sit out for a day or so but we had seen no reason to wait. As far as walking down the mattress. We never had seen it happen to our bed at all. It stays in place pretty well. For what is it worth, this was worth every penny spent and then some. We could not have imaged how much of a difference it has made.