Love this bed! We have an extra thick king mattress  originally thought a boxspring would be required but it was WAY too high on this frame. We ended up adding 8 extra slats (it comes with 4 or 5) and legs for extra support and positioned our mattress directly on the frame. Im rating this a 45 because one of the slats that came with the package (wooden cross supports) wasnt quite long enough. Overall, would recommend.