Better VST compatability, better stability, better recordings for live recordings connected via the mic or line input. Easier to sample voices or whatever you want to the right tempo. What else more do you want? Oh yeah, and it comes with more synths .
Not really. You can tell it not to snap to the grid[although most of the time, you really want to snap to grid and base your melodies and harmonies according to the bpm and the grid size.