Visitors can post reviews of any SHO product they purchased. Please do not bash vendors or use this as a way to "get back" at a vendor for wronging you by posting false information. Users can read through posted reviews, post their own opinions, or post their own reviews. You can upload a picture to accompany your review.
Just because someone has already posted a review on a product you recently installed doesn't mean your input isn't worth it! Post a comment on the existing review or make a completely new review (for the same product). When posting comments, you have the ability to re-rate the product as well.