Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Best Concept Rock Album of All-Time

For those unfamilar with "Dark Side of the Moon", the album has been on the charts longer than any album in history. If you wonder why, then you have not listened to the album. There are very few artists, who bring rock music to such a high-level, as Pink Floyd. "Dark Side.." can be described as a very thought-provoking and beautiful album, which touches the soul. At the surface level, the album is dreamy and strange to the casual listener. With an open-mind one can travel into the psyche of the individual.