Just FYI, if anyone's considering using them... the unit I received was not only reasonably priced and arrived in < 2 weeks, but seems to be working very well. Time will tell how long it lasts, but for now, she's purring like mildly irritated mountain lion.

 

I hope it's the trick. Random issues are hard to claim resolved right away.
Did you replace the relay(s)?

 

Yup, all of them marked as having anything to do with the fans. 4 of them, I believe. When it would overheat, the fan would turn kind of half-assed, despite being a new fan and a new wiring harness and relays. Now it will suck cigarette smoke into the grille from 6 feet away. I've also noticed my mileage mildy improved. 1500 miles so far and 0 issues