The IC Mister kit has three significant benefits over the simple push button activation of the washer pump.

First it allows you to go hands free and the system still operates. There are times where I want to flash my lights, honk the horn, something with my hands where they are not in the necessary location to do so, and I ended up not doing what I want. With the automatic system it takes care of turning the pump on and off, no missed opportunities.

Second, it is set and forget. You don't need to think about spraying them because the system takes care of that for you. This is similar to the first point, you need to remember to turn it on, and then physically move you hands to a position to activate the system if it is a manual button push.

Third, the system is monitoring stuff that you aren't, or cannot. Do you constantly monitor the load you are putting on the car, and can you assess it to the point of being able to say when the car passes a particular load threshold? Do you know what the temperature of the IC is, and how that compares to the outside air blowing over it? Can you evaluate those two inputs and then spray the IC's when the conditions are right?

The flexibilty of the automatic system is nice. You can adjust the temperature so it only needs to be slightly warmer than the outside air, so that essentially any time the duty cycle threshold is passed the system activates. Or, like I do, the temperature is set just above where the IC would be at steady state cruise, so if the temperature rises at all above cruise temps that trigger is now set. Then once I'm a pound or two into boost that trigger fires. Both of those conditions have to be met. If I'm cruising down a road and want to pass someone the system probably won't activate because even though I go into boost, the IC's aren't above their threshold. And by the time they are, I've returned to cruising, no more boost, and the airflow alone can cool the IC's.

The overall benefit from the system is to only spray the IC's when they need it, thus conserving water in your tank, and doing so without any active involvement on your part.

National Motorists Association