I have two of these low temp switches waiting on some Zip Ty second generation waterless coolant to arrive, I will R & R the switch and change the coolant on both my bike and wife's bike. I used the 1st generation in our Husky 511 and 310 - both known to run hot. We run our bikes often in the desert heat, low speed, technical rides that should boil our coolant, but I have never had a boil over or lost a drop of this coolant from boil over. Also supposed to be very corrosion resistant for 7+ years - no flushing needed for 7+ years.
I think if a guy is going to change the switch - makes sense to switch the coolant as well. This stuff boils at like 350 degrees~