YSL Nude Avant-Garde (91) is a warm pink with a luminous finish that is limited edition and retails for $38.00. In comparison, Bobbi Brown Retro Coral is a warm coral with a cream finish that is permanent and retails for $40.00.
Bobbi Brown Retro Coral is 85% similar — it is less shimmery, lighter, more pigmented, warmer.