The difference, spalding, is the control paradigm...

For instance, on the MotifXS, probably the most 'chord following' of all the WS's, there is no way to trigger loops as fills in the arranger sense. That is, you can, on an arranger, drop into a fill DURING a bar, and everything will stay in sync. On the MoXS, you either have to cue the fill up a bar in advance, or you are out of luck.

What arrangers have is a very natural, musical approach to triggering loops (that's all styles are, really - little MIDI or audio loops that follow the chords), but we have no really contemporary sounds and styles. The WS's, OTOH, have very contemporary styles (that's all loops are, really ) but a completely unintuitive way of triggering them.

First keyboard that combines the two cleans up, in my opinion. It can be an arranger company if they make the effort. Somehow, though, I doubt it. And next to 'home organs' from the sixties and seventies, in the Museum of Obsolete Instruments pretty soon will lie the 'arranger'.

From Nedim's reply, it is obvious that arranger manufacturers are only concerned with their existing markets. While WS manufacturers are concerned with innovating and GROWING their market... And it weill only take ONE WS to adopt the arranger control paradigm (software loop players like Live already allow you to drop into fill loops like arrangers do) and everybody will drop arrangers faster than a hot potato...

Trust me Nedim... your market did NOT come looking for you. YOU went to them, provided the service, and THEN they came. That's how it works. Nobody buys a truck if they want a minivan. You have to build the minivan before they will buy it. And the arranger manufacturers have to build a contemporary arranger, before that segment of the market (young musicians with money$$$ ) will buy one. You can't expect them to buy things better suited to their grandparents, and just HOPE that better styles are developed...