audio tracks are fantastic. they've helped me get over a MAJOR hurdle in my own production - use of thick, dense samples with a lot going on. these samples are not good to chop, they're better to loop in small pieces.
slicing these things is irritating - you can slice and reprogram all you want, but odds are it's going to sound like it's been sliced. when a sample is OPEN (ie just the drums, or JUST the guitar etc) you can slice/reprogram without anyone ever knowing. when there's more going on, this is exponentially more difficult.
audio tracks make this possible - in conjunction with a software that allows stretching like Reaper or Ableton. in reaper, you can drag a sample onto the grid and stretch specific bits of it here and there. this allows you to form a bunch of perfect loops and correct slice timing variations in the original recording before importing them into jjos2.