In my oppinion all of the real tracks have improved greatly especially accoustic bass. The early bass tracks seemed to have intonation issues. The jazz bass and drum tracks now sound about as good as my favorite live players and play the right notes and don't give me any aggravation. The accoustic piano parts are now usable but not up to the standards of the bass and drums. Piano is very dificult to record. With the new stretching technology the quality of all real tracks is much better at all tempos.