Did it a couple of days ago, and was actually wanting some rain to test it out! This baby is supposed to automatically adjust the wiper interval to whatever the actual rainfall on the car is.
Well, on the way to the annual oil change today, we got the perfect test delivery, from light sprinkle to heavy rain. And it seemed to perform well, only occasionally taking a little longer than I would have liked before wiping.
The little click from the relay is a little disconcerting, but I'm sure I'll get used to it (I hope it's normal).
The other thing to be aware of if you're thinking of this mod, is where you put the sensor. I put it directly above the mirror mount, which puts it over the next-to-useless radio aerial in the windshield. As it turns out, it can generate substantial interference for AM radio stations, but doesn't do it all the time.
The hardest part of the install was running the wire from the sensor to the relay panel under the interior body parts. You never know what you can reef on because it's held on by a clip vs where you have to search for some hidden screw. The 2nd hardest part was zip-tying all the extra wire up over the relay panel. Man you've got to be a contortionist to work in there!