Many people had good experiences with Holden grey motors too
Not true, not by today's standards. 50% have average or above experiences but in the 60s even private owners traded their Holdens before 3 years, most were rusty by then. I ran a servo and in this small town [then] they were everywhere and we all made a living servicing or selling parts for Falcon/Holdens. My trade is radio/radar but soon became a useful mechanic on them.
Most needed a valve regrind @ 25,000 miles and a new short motor at 50,000. A mate in another servo always had a Repco short motor in stock.