MAC Ambrosial is a warm purple with a natural finish that is discontinued and retails for $21.00. In comparison, Estee Lauder Thrill Seeker (420) is a cool fuchsia with a pearl finish that is permanent and retails for $32.00.
Estee Lauder Thrill Seeker (420) is 85% similar — it is more shimmery, darker, warmer.