It isn't the shiny look of a fresh aluminum head that will grab you, it's the nicely shaped port and bowl forms, the quench combustion chamber, and the deeper, angled spark-plug position. Then run comparison flow bench testing versus the ubiquitous 906 casting. That exercise showed 291 cfm of intake airflow against 233 cfm for the 906 casting. and 223 cfm versus 171 cfm on the exhaust side.
