one of them was probably mine.
I spent a weekend in the rockies and the Hayden was roaring almost the entire time...the last day started at 13,000', below freezing. Fan was on from startup, through engine braking down thousands of feet with no load, temp wasn't even high enough to open the thermostat most of the time so there was no way the air coming off the radiator was the 170F it's supposed to take to engage the fan clutch. I swapped it for the USMW as soon as I got home. I stil want to go electric but it at least works the way a mechanical fan is supposed to.
Out of curiosity, where did you get your Hayden from? I am not trying to undermine that you may well be right about issues with Hayden fan clutches, but if it was Amazon - I have had very poor experiences with their automotive products (regardless of brand).