Like others commented, there was one place where the holes didn't line up, and I really really muscled through it.  However, the bed is otherwise very sturdy (I chose it bc it had a higher weight limit compared to wood or wood composite daybeds).  It's beautiful in person, and bc it uses legs instead of a spring up system for the trundle, I feel better that it won't fall ;). The engineering design is really elegant, right down to the pieces to lock the metal slats into place.  While I wouldn't want to take it apart and reassemble it, I am confident it will last a long time.   I used two 8" mattresses no problem, and maybe could have fot 9".  Love the option to have two twin guest beds or one king--just recommend a mattress pad when combining to smooth the crease between mattresses.