Without having extensible knowledge about it but taking advantage of the hour difference (our American friends are probably having breakfast or are sound asleep right now), I can tell you that OMB is a software that can take any synth (Soft or Hard) and add arranger functions.

Along with edit capabilities, a style aditor (which many arrangers themselves lack) and so on. Accepts Yamaha styles, the software is must have if you have a synth but sometimes you want quick styles and inspiration.

I suspect many of the guys or gals here would kill if you'd threaten to take it from them. It is also cheap.