Roger, but you need to look at the whole package price, and do the math not just look at the cost of the heads alone. The Autozone discounted Edelbrock heads are in the same price range +/- a few 10's of $ as the EQ Magnums so any valvetrain parts may tip the cost advantage one way or another.
As do iron heads; happens all the time with both.
The issue with AL is that there will always be corrosion between dissimilar metals and that gets worse as the anti-corrosion additives in the coolant wear out after 3 or so years. One metal or the other will be 'sacrificial' and will corrode. In an old iron engine with a brass radiator, the iron is the sacrificial metal, and so all the corrosion is inside the block and heads.... which is why old engines look so crappy in the inside of the water jackets! With AL parts, the aluminum is the sacrificial metal and so any head or rad will experience corrosion This is why AL rads are so much more prone to plugging up versus brass rads over the long term if the coolant is not changed every 3-4 years.