Amazon and Does It Really Work offer customer reviews and complaints regarding the flex belt. Amazon allows customers to review products once received, making it is a reliable third-party site that is not affiliated with the brand itself.
As of June 2015, Amazon has 428 customer reviews for the flex belt, with an overall score of 4.1 out of 5 stars. Customers leave comprehensive explanations for their ratings, which include their personal experience with the flex belt. Does It Really Work? is a review of the product that allows users to give a thumbs up or a thumbs down regarding whether or not the product worked for them. There are also additional reviews in the comments section.