I bought this mattress in February 2008 after looking at some reviews about it online first. My boyfriend had bought a double one a few weeks earlier and the corners never expanded all the way so I was iffy about buying one for myself. I decided that if i had issues with it I could always return it to Costco. To anyone that has problems fully expanding this topper, you need to read this. I left it in my room the very first day on the floor. Since it was February, I had my portable fan heater blasting on in my room and it was very warm. After about an hour my mattress expanded to the full three inches, except for 2 corners and a bit of the bottom edges. I was surprised, then my sister suggested that maybe the heat helped it expand. Remember the instructions that come with it? It says colder conditions may take time. What it should have stated was lots of heat needed!!!So I took my portable heater and pointed it in turn towards any part of the mattress that had not expanded and they started to rise after about another hour. I think the problem is, if a room is too cold the topper will stay compress and since the corners are the ones totally compressed in the vacuum bag than in the middle of the topper, thats why it takes longer to expand. I also want to point out that I also used my hairdryer and blasted the parts that needed to expand. After two days in a sauna-like room I was able to sleep on the foam topper which was finally 100% inflated to the full 3inches. Weeks later, my parents bought a queen size topper, and I helped them expand it in my room (they have no floor space) doing the same thing I did with mine and it also fully expanded, pointed corners and all.If you have enough patience and time to do what I did, you will be fully satisfied with this topper. It has let me have many restful nights without waking up. My sister has said that I never wake up anymore when she comes into my room to borrow something, say in the morning. I used to be a light sleeper, and the slightest opening of a door would awaken me but not anymore. This topper has also helped my back because I put it on top of a 14-year-old spring mattress that started to become uncomfortable. Good luck on your topper and I would recommend this topper!

Recommended: Yes