We bought this topper about 2 years ago to go on our waterbed. The topper rolled out and was full size in just a few hours and there was no smell as many people say with the foam beds. This was extremely comfortable, soft and conforming. We used it on a waterbed and it was like sleeping in a cloud, just heaven. I also used it to sleep on the floor a few times and it did help considerably, I could still feel the floor but it made it almost comfortable to be on the floor, and I have severe back problems, arthritis, and fibromyalgia. I just purchased a 12inch foam mattress to replace the waterbed because we liked this so much, we plan to use it on that as well. The only thing I have to complain about is that it says it is a 5.5inch and mine only measures 4inches. I assumed there would be a discrepency however, that is why I purchased the biggest one I could find! I would absolutely reccomend this to others, EVERYONE who has been to my home has checked it out and loved it.