ceramic coated headers on break in

They say not to break in with them because too many people think that getting the car fired and up to RPM is good enough, which is FLAT WRONG.

Not enough ignition timing during break in is the biggest reason exhaust temps spike to high levels and damaging coatings. Rich or lean plays a much smaller part in the equation.

Header manufactures prefer to not warranty stuff because of user error.

I've broken in a bunch of engines with coated headers and never had an issue with coatings burning off.