I think they are OK, and I do notice when they are on - couple times I have turned them off because my azz got too cool! If you move yourself ever so slightly away from the seat back, so you are not pressing directly against it - that's when you really feel it. Not suggesting to do that permanently, of course but just so you can tell they really are moving cold air. You really need to have the car AC on for them to be worth while using, otherwise they are just blowing unconditioned cabin air. They are not as good as the ventilated seats in the Toyota Avalon I used to have, but they are still good. Elder, agreed - at 3 blue lights power, you can hear the fan.