back to the starter issue. You mentioned heat soak, and I've had some bad luck with that too.
I had a new Kragen starter go bad after a long road trip. It just wouldn't click over until the truck cooled completely. Then it cranked right over.
So I returned it for a new one, but this time I got a new plastic cover for the solenoid and wrapped the whole starter with a heat blanket kit. That was 2 years ago and I haven't had any trouble since.
But I definitely agree with all the posts about the old time mechanics actually fixing problems, and not just throwing parts at something, crossing your fingers, and hoping the owner sells the car before your installed junk breaks.