The covers are absolutely fantastic! Oh, I love the third and fourth one. The Goblet of Fire and Azkaban on the cover, they're brilliant!

The first one is sort of scary looking, the stone and it's redness. I love the second one's cover as well, it really resembles the book and movie. I like how instead of focusing on the whole book, they each just take one piece from the story and put it on the cover. Unlike how it is in the childrens versions.