They are both bolt onto OEM. They both have similar response, make similar power and require the similar levels of boost to do it. The turbos will reasonably close as opposed to different ends of the footy fields. There is only so many ways to can skin that cat in a OEM frame.
Did those same people tell you that;
Heat can be controlled by the tune/boost levels & overall cooling setup of the car.
Housings/wheels are the contributing factors. They are NOT the single point cause.
What temps are we talking about here btw when the detonation occurs? I’m assuming you are logging it to safely say it’s not the tune?
End of the day mate you can here asking for help. Several people all saying basically the same thing, which mind you, is coming from the information you are giving us. Seems odd to me that a few different people would all have the same view. If it was not clear cut, then there would be many theories.
It’s a 15 second job to pull 2 degrees of timing with a PFC, and 30 seconds to pull 2psi. If the detonation stops, I’d be surprised if you should also see a drop in temps.
End of the day it you that'll be going and spending $2500-$3000 if you go the option you are looking at, and it sounds like you’ve already made your decision given the fact you don’t want to take anything on board that anyone is saying.