[pantulis]

I would add another keyboard category, the workstation synthesizer (Fantom, Kronos/Nautilus, Montage...) which also let you perform solo and allow you to create your own productions (the Kronos will even burn a CD!)

Supposed to be the flagship product, I find very interesting how musical instruments manufacturers carefully differentiate the features between arrangers and workstations.

[xhevahir]

There's a lot of overlap between the Montage and the Genos. A lot of the "Performances" and "Arpeggios" in the workstation are derived from Yamaha's arranger keyboards. Arranger keyboards, though, are anathema to a lot of musicians because of their association with the kind of one-man-band acts that perform in nursing homes, airport lounges, Oktoberfesten, and so on. (It's no accident they usually have whole banks of presets dedicated to genres like Schlager and Polka.)

[klodolph]

I think of the Montage/et al as fitting into the synth category. I have an older keyboard like the Montage.

There is feature differentiation, sure. But I think the biggest difference between product lines is the controls. Arranger keyboards need convenient buttons for changing song sections. Synthesizers need dedicated controls for sound design. Stage pianos have dedicated buttons for the common sounds—acoustic piano, electric piano, and electric organ.

If there is a keyboard that “does it all”, I’d guess that it’s something like the Genos. It costs a couple grand more than the Montage.