Femme Fatale - Album who made dubstep popular, with one best singles of Britney's career, a pop masterpiece, copys of the album exhibited on the Louvre Museum, MET and Rock n' Roll Museum
Born This Way - The most overrated album of pop history, marked by marketing shenanigans, responsible for Amazon's bankrupt.
4 - Good and experimental album, a couple of Grammys, embarrassing single performances.