I guess some don't comprehend what the OP wanted to mean by using the word clone. Artists don't have to be like Britney or Beyoncé, but some of them were marketed as they were. Jessica Simpson, Mandy Moore, Selena Gomez, Miley Cyrus and even Xtina were marketed as Spears was back at her early beginning. While Rihanna, Amerie and so many others were marketed like Beyoncé as well.