do you have more information on this?
The radiator is about 6 to 10 feet away from the thermostat, so its not a physical problem.
That would leave heat. I would hope any aftermarket radiator would hold up to the 250ish deg that our car can throw at it.
That aside; I have been running a Wizard radiator for over a year on the same 170deg thermostat that was in the car before the swap. (Yep, I swapped the failed 180deg factory tstat for the 170deg tstat probably close to 3 years ago.)
Apexes are a lot like relationships. So tough to get right, so easy to see where they went wrong.
The secret to a long life is ------- not dying.