Instruct: Classify Amazon reviews into positive or negative sentiment
Query: This recording is the best of Tchaikovsky Op. 50.

There's a reason this won a Grammy: lyricism, flawless virtuosity, rubato and perfect agogic usage. It is a grand slam in interpretation, taste, and for its time, engineering quality. My credentials - I'm performing it in a month and have a masters degree from New England Conservatory in piano. Sobel's review is ueless. My violinist emphatically agreed: the best recording of this piece that we've heard. Put superstars together: fireworks.