without being one of the few lucky guys who had several arranger along the way, i could say few words about the only two i owned: kawai fs630 and korg pa50.
kawai fs630
(i had it for about four years, old model, but pretty good sounds at the time. it was 1991 when i got it i guess)
pro: good sounds, add-lib (sort of phrase bank for every style), light weight, but quite powerful speakers.
cons: few styles, only 25. no fill in. no variation. bad buttons. bad keys. no midi at all.
of course this model was not professional instrument, but was my first normal size keys keyboard. (my very first "electric organ" was a casio mt70, small keys)
korg pa50
i got this last year may, and had it for about six months. no need to present it, since all of us know about it.
pros: the sounds, the styles, the design, the keys (not extraordinary though), large display, the way you can assign functions to pads and to keys velocity, the fact you can erase unwanted factory styles and replace them, the joystick.
cons: the operating system, the hiss coming out thru the line out, the two bad buttons, not ideal midi, the fillins stupid action, the only two fills.
was very briefly, but this is what i experienced.
now i am waiting for a new instrument. e60.