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Dis-similar metals, aka steel & aluminum, don't generally mix well. Not sure the technical term but over time the steel sort of eats into the aluminum head surface. Also the steel gasket is a harder material than the aluminum head which means the gasket could imprint itself into the head.
Doesn't seem worth the risk with high dollar heads.
It's called bi-metallic corrosion.
I wouldn't sweat it if you use coolant and not straight water as the coolant has corrosion inhibitors. Also, it really doesn't matter what head gasket you use, in regards to corrosion, they all will have a dissimilar metals issue.
They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.
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