Sport at all times. Just have pedal discipline, you don't have to be mashing on the pedal all the time. Having access to instant light speed torque is a safety thing that I want in my back pocket at all times if needed.
Sport usually. I use chill when I want to maximize efficiency or am in a crowded situation such as a hectic parking lot with lots of people or odd parking situation. I find it helps me.
My wife prefers chill since she is more accustomed to drving a Prius or Chevy volt.