This is the second memory foam mattress I've ordered from Overstock. The first, a queen-size, was just terrific. It did need to offgas, but only for a couple of days, and then it was good to go, and very comfortable. About a month ago, however, I ordered the same thickness in a full size, and it still can't be used. In fact, we can't even go into the room for fear of passing out. I'm sure it'll be great in another month or two or three.