We bought this for our queen size guest bedroom bed. The mattress we bought was cheap, and very uncomfortable. This topper definitely made it much more comfortable to sleep on. It was shipped very quickly, and I guess I didn't realize it came in two pieces until I opened it up: the blue gel foam, and the white puffy mattress cover that goes over it. I took others advice and unrolled the foam directly on top of the bed, and I'm glad I did - it was very heavy. I let the foam piece air out on top of the bed with the window open for about 2 days, and by then, the smell had greatly diminished. I put the white piece on, then the fitted sheet, and there was virtually no smell at all. I slept on the bed that night (while my husband snored in our master bedroom), and the first thing I noticed was that you really sink way down into this topper. It relieves all the pressure points on my shoulders, hips, knees, so I didn't need to toss and turn as much. I didn't mind the sinking/enveloping feeling that much because I didn't have to move very much throughout the night. When I did turn over for a complete position change, it was more of an effort to pick myself up out of the foam and turn over. I was not too hot or too cold, the temperature was just right. I'm glad we went with the gel for that reason. This topper does what we bought it for: makes our guest bed much more comfortable, and not too hot.