I ordered this memory foam mattress since it was a Christopher Knight brand. This is my first memory foam mattress. My daughter-in-law orders from Great Offer Stock all the time, so I have been ordering from Great Offer Stock since last summer and am usually very satisfied. I unpacked the mattress and let it rise for more than 48 hours. I waited for over 3 days since all four corners of the bed did not fill out like the rest of the bed. I finally accepted the amount the corners filled out and started sleeping on it. It is a queen size and I am the only one sleeping on it. I am a 200 pound female and placed mattress on platform heavy metal frame that was the sturdiest one Great Offer Stock sold. Within 2 months, the side of the bed I sleep on is not firm like the other side of the bed. It is still comfortable and I get a better night's sleep than on my sleep number bed, but I am disappointed that this is happening. Customer Service said I would need to deal with the manufacturer for the warranty. I am going to add a thick piece of plywood under the mattress to see if this helps, even though the metal spring platform frame is supposed to be adequate. My son and daughter-in-law added plywood to their platform frame prior to even sleeping on the mattress, so maybe that is what is best for memory foam mattresses. They purchased all their furniture from Great Offer Stock, and also my son is much heavier for me, and they have had no sagging with their memory foam mattress. Mine is 13 inches and I think theirs is 14 inches and queen size like mine, and I am only one person. So, that is why I only gave 3 stars.
