There seems very little downside to choosing this fixed setting so I think many of us have always our had our keyboards set this way - often for so long we forgot it was originally a choice. It has a coupe of advantages, auditioning styles quickly as per the OP, but also allows you to smoothly change styles while live playing, which can be both fun and in the right circumstances, better than just changing style variations. It's a setting I think most Yamaha arranger players should consider.
Mike