Yes it worked rather well with an old E50 and a Yamaha S90es. Hitting the buttons was not that onerous, you could not do multiple quick changes but I could get by okay.

I never need to change anything else apart from variations, as all keyboard parts and tones came from the s90, and in fact sometimes all that came from the E50 was the drums.

The MOST important and most basic is an NTA and Roland for whatever dumb reason left it off. And no, the GW series are not the most budget, check out the pricing of some of the lower end Yamahas, and I believe even they can allow the arranger section to be played by an external keyboard.

This is like the time Roland released a new keyboard but reckoned no-one needed a sustain pedal socket.......so they left it off!!!! That was back in the early 90's I think.

And to claim the GW series are NOT arrangers (they are synths, according to Roland) so therefore do not qualify for NTA ability, OR patch changing. BUT they are being marketed as arrangers???

Only Roland. They sometimes do brilliant things, but then do really dumb things.