I cannot tell you about the Sunon 48x36 bookcase, because we received the 60x36 bookcase.  We could have returned it, but the boxes were so heavy (77lbs) that we decided to keep them and rearrange the room to accommodate them.  I can say that the bookcases that we did get from the same company are very durable, look good, and were easy to put together.  If they were what we ordered, they would get a 5.