I have just unwrapped this item and felt compelled to write a review because of all the negative ones I had read prior to ordering.
As you can see from the description on amazon, this case is made to fit the 13.3" Macbook (which was discontinued June 2011), NOT the 13" MB Pro - although as I believe that model is smaller it should do the trick more or less. As far as I can tell, this is a perfect fit, and is as snug as you can get without the zips catching the Macbook inside. Granted, the case isn't as thick as it could be, but its perfect for some extra protection whilst being transported around within a larger bag.
It's good value, and certainly fits its purpose - I can only assume all the one stars on here are because of a misunderstanding around which model this is intended for.