I try to WRITE originals on my PA-1X (and did many on my old Roland VA-7 - wrote AND recorded - turned out great.

They're a great songwriting tool and it is THE reason I continue to buy arrangers (as opposed to Workstations/Synths).

(I know that wasn't the question, I just wanted to contribute in some way to the conversation...)

I think many people would either use a live band, or having written/recorded on their arranger would then play to the backing track and perhaps supplement with live musicians.

When we get our home studio completed, that's the way we'll do it - backing tracks with as much "live play" as possible.