Instruct: Classify an Amazon review into positive or negative sentiment.
Query: Awful product!

I read all the reviews, good and bad. And decided to try the product anyway. The negetive reviews were right. This product is awful! The trays are cheap paper type material,they do not stay on and the gel burns your gums. I took them out after 5 mins and my teeth felt sensitive already. I am taking these back tomorrow.Going to try Crest Whitestrips next.