I think it would be interesting to hear what kind of musics those that play Ketrons primarily play to your audiences...

I just don't feel a blanket recommendation without this fact is of all that much use... Some arrangers seem better for smooth jazz, some for rock and hiphop, some for bigband, etc.. To be honest, if someone is primarily playing country or R&B, an arranger that excels at bigband is probably not that great a buy, and vice versa.