Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Poetry in motion

There are now two "best of 1999" albums on my list. Prince Paul's Prince Among Thieves still is one of the most important conceptual pieces for hip hop in a long time. But for straight brilliance, Black on Both Sides shines bright. Mos plays the vibes, precussion, croons, shouts like a punk rocker, drops the coldest flow I've heard in a long time, and has insight to match it. He's a little more militant this album, which is good for a mind as sharp as his -- New World Water, Mathematics, and Rock and Roll are all incredible. But so is everything else... Mos Def is just hitting his stride. This is the album of 1999.