Urban Decay Backstab is a cool plum with a pearl finish that is limited edition and retails for $18.00. In comparison, Marc Jacobs Beauty Merlot Blow (380) is a warm purple with a satin finish that is permanent and retails for $26.00.
Marc Jacobs Beauty Merlot Blow (380) is 80% similar — it is darker, more muted, less glossy.