Schema.org Customer Review widget

Hi

I was wondering if there is any review plugins out there that allows customers / visitors to add reviews , preferably with star rating system and a field for comments ) . Ability to add the review to a post/page via shortcode would be a bonus. I came across multiple plugins that allows authors to add schema.org review in to the post but none that allows my visitors to do the same. It does not have to be a free plugin , if it does the job right I don’t mind paying for it.

Thanks
Saijo