Marielou provides a detailed review of the Duo Brow Brush by Browly in her video. She starts by mentioning the convenience of having a duo brush with an angled side and a protective cover. She also highlights the versatility of the spoolie, which can be bent according to preference. Marielou appreciates the tight bristles and the flat top of the brush, which allows for precise application. Overall, she finds the brush to be of good quality and easy to use. However, she briefly mentions some difficulty in initially accessing the product. Despite this minor drawback, Marielou concludes that the Duo Brow Brush by Browly is a great tool for applying powder, cream, or gel to achieve well-groomed brows.