The problem I have always had with arrangers personally is the quality and feel of the keys. I just don't like those little cheap plastic keys. They break too easily and wear out in no time at all, especially if you use it every night. Example: Uncle Daves last arranger(and the one before it)...How long did he have it?
I agree that they sound alot better these days, but if you are going to rely on it night after night, its just not good enough. I have slammed arrangers before on this forum but Im not intentionally slamming now. Im just stateing my experience. When I worked in the studio, every once in a while we'd get a musician that uses an arranger keyboard who someone thought was very good. We'd get them into the studio to record and we would end up finding that most (not all) were just these 1 finger wonders with an arranger keyboard. Im not putting them down, but it wasn't what we were looking for. Im not going to invest in a musician who uses default (or even purchased) arrangements as the body of their songs. Nothing against arranger keyboard players, it was about marketability and originality. If you didn't write it(or even play it), why would you want to record it? I don't even like sampling for that reason. I can't release a preset arrangement. period. That is why many arranger keyboardist have such a hard time getting their music released.
Back to my first point, I think when Yamaha calls a keyboard a "home" keyboard, it has more to do with quality and durability of the keyboard than sounds, especially recently. If I was making a living playing, I would want something that I can rely on night after night. Something that I could use for several years not months. And if I were making a living doing that then it would be worth the higher cost to buy a "professional" keyboard, one that was made to take a beating night after night. I think of it as an investment in yourself as a musician, one that would pay for itself in time.

It all good,
DudeManCentral