Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Just Another Riff Book

I have about seven years on the guitar and am always looking for new material to study. I ordered this book, flipped through it a few times, and put it on the shelf with about twenty other books that cover the exact same ground. Just your generic, run-of-the-mill, riff collection. The majority of the riffs are just scale runs in different keys! I suppose if you're just getting started and looking for blues/rock ideas this may work (though there are thousands of these types of books out there).