Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Heavy metal Floyd

For Pink Floyd, this is probably the consistently heaviest album they ever made. Lots of furious energy in this one. The 'Pigs on the Wing' songs introduce and conclude the concept of the album, and are not bad in that context, wisely kept short. 'Dogs' has some very good solos by Dave, but isn't their strongest compositional effort (and is half of the album). The second side opens with Pigs (3 different kinds), an excellent song - good bass riffs, and an original arrangement, with a blistering guitar solo at the end that I feel is Dave Gilmour's finest moment. 'Sheep' opens with a nice electric piano solo but turns into a freaky hard rocking tune, replete with hypnotic middle part and ends with another excellent Gilmour solo.