we like the storage bed and all but came across a strange sizing issue when we bought a new king mattress to place on this bed, the frame and slats are about 3" longer (width-wise) across the bed. this leaves a gap between the mattress and the edge of the frame where the slats are exposed, figured everything was standard sizes, guess not. We also decided to place a low profile boxspring on this, as the slats are really flimsy, helped with sagging.