i thought the same thing about that thermostat and didn't go for it. i am using the 1.5k ohm resistor right now and the max temps are a wee bit lower than when using the 1.8k and i do seem to notice that the fans kick in more often. i'll keep it this way for the summer and switch to the higher one in winter.
1993 300e-2.8 - gone now <sigh>
"Do not adjust your mind, it's reality that's malfunctioning"