To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
Really good product, before buying I thought that if I'm not comfortable with this product I"ll return it but It's really surprised me. It's easy to use and work really good, but it should be more cheaper.