I have always had ventilated seats in all my cars, I had them in my 2017 model S and I loved them, I had them on any time the weather was not cold. My wife hated the ventilated seats, she kept the seat heater on all summer, I guess everybody is different. I just got a new Raven Model X and am worried about what I will do next summer when it gets hot again. I bought a ventilated seat pad that plugs into the cigarette lighter which blows a lot of air but is a pain because it goes over the seat. I wish Tesla still had the seat ventilation built in.