Due to an old dog that can’t go up the stairs, we needed a sofa bed that would be comfortable for every night use and so far, this has not disappointed. (Around 4 months of use so far) We got the topper too which I fully recommend. The back comes down to form half of the bed which doesn’t lay fully flat at the part where it joins the seat part which makes a bit of a dip which is slightly annoying if you’re sleeping on that side. The other side (the seat part) is flat and very much like any mattress. It’s quite firm which may take a bit of getting used to if you’re used to a soft mattress. It is proper double bed size though which is great. There’s a little bit of space under the seat but it’s not enough for the cushions so when it’s a bed, they will need to be elsewhere. It is fairly heavy to change it from sofa to bed and vice versa as you need to lift the seat part up to get the legs up or down. As a sofa, it’s comfortable and looks absolutely gorgeous.