This is a great story book. The 5 stars is for that.
I bought three editions for different kids: Good Night, Gorilla (Picture Puffin Books (Sagebrush)), Good Night, Gorilla, and Good Night, Gorilla (oversized board book). The Puffin edition is bound in a way that makes it difficult to open flat. The paper is thinner than most good hardcover children's books. The two board book editions are very nice. You also might want to try the regular hardcover edition.