Seems like Yamaha is FAR ahead of Roland in this regard. The XS needs so little corrected for it's OS to be arranger capable, and then it's simply a case of newer arps (which could probably be imported fro the MIDI output of current arranger's patterns, Intro endings, fills, etc) to make it usable.

But without Music Finders, lyric displays and a revised system for accessing those styles (oops, arps!), they still have a ways to go to equal the shear user friendliness of the arranger.

But Yamaha have made a start... Roland, not so much