So its all about what mode gives you the best feel from the bike and has the level of electronic intervention you are comfortable with. No right/wrong here. I could see that being any of the three main modes depending on the rider and conditions. And in some conditions, maybe even rain (like riding in the rain).
I do think it comes down to feel and perception (at least on the '12's). I remember testing out race and slick and going back and forth between which one I thought was smoother/more responsive. I decided it was all in my head and pretty much keep it in Sport now. I want the biggest safety net