Squeak, for an example of how much better quality is available now ( but not in an arranger ) check out the demo cds from sample co. Spectrasonics. Try selections from "Hans Zimmer guitars" or"Liquid Grooves" or "Retro Funk Drums"or "Vocal Planet ". The quality is astounding. And yes, someday, this quality at psr550 prices! The future is coming on fast and before long we will regard todays' keyboards as quaint toys!
Till then, we can enjoy what we have.
Bill