Whether selling a product or providing a service your business is constantly subject to judgement from customers, be it existing customers or potential new customers. There are many independent review sites such as Trip Advisor and Trustpilot that allow people to post company reviews and add a score (usually out of 5) for products and/or services. These websites are quite popular however the issue is that anyone can post a review, whether they are a verified customer or not. This means that you open yourself up to the possibility of negative feedback from false customers, these could be left by your competitors to purposefully reduce your score.
Reviews can, however, be very useful. With the way of the modern world most of us take time to read and compare product and service reviews prior to any purchases to make sure we avoid any negative experiences.
One option would be to allow customers to submit a review but have your website set up to have to manually approve any reviews, that way you can check that the review is genuine and that it is suitable to be published.
Many websites publish testimonies, these are positive customer quotes and are designed to promote your business through positive reviews from past customers.