The ever-so desireable 308 Heads

The biggest concern is the aftermarket/aluminum heads durability. You won't see them being rebuilt time after time like the OEM cast iron.
The HP Oem heads will still command higher value for the #s guys.
Curious what you think is wearing out faster or preventing rebuild on an aluminum head than on a cast iron one? Valve guides, seals, and seats are wear parts and replaceable on both.