I would think that aluminum heads would be more easily pitted by predetonating fuel. they must be using much richer fuel scheduling. If it ever gets lean they will have major problems..... I would think. The knowledge I have on the subject is old school but has been common knowledge about compression and fuel octane since I was a kid. Of course we didn't have computers checking things like the O2 level in the exhaust gases to make sure the engine doesn't run too lean. It may very well be possible, I guess, for the ECU to make running lower octane fuel in higher compression engines safe. By keeping the fuel mixture on the rich side and retarding the igition timing on the fly.

Rule of thumb is.... If it's not pinging, you're okay..... That's a rule that I don't think will ever change.