I really dug the the first track (Illmind), the rest are interesting. Though Andrew's track (last) is bizarre. But you get a glimpse into each's production flow and style - which is always cool.
What's cool is that they used a full song's stems (free sample download below) to do this. Has guitar, bass, sax, etc.. Great idea to start offering a full song, played by real musicians as a sample pack.
Get the 600mb sample song/pack here