Cohiba (Esplendido), Monte Cristo (#2), and Romeo y Julieta (Churchill) are the three most faked cigars in the world (all of which are 7x50 in size or close to it...why fake a little one?!). The only place I'd trust buying a "real" Cohiba is at the Partagas factory in Habana, where they are rolled. Anywhere else, including a certified "Habanos" store entails a significant chance you are getting a fake.
There are other brands rolled in the same factory that are very good but not as frequently faked and are therefore far less risky.
When you do get a good one, a real one, it is the closest thing I've found to religion....and that's coming from a devout born-again atheist.