Big TFS fan. Joe has ported some TFS heads for me that have done some great things. My last 445 made ~620 hp with them, a 10.2:1 compression ratio, and a 6000 rpm peak with a Performer RPM. Joe is right, we get about 360 cfm @ .700" lift with a 178cc port, and a 2.190" intake valve.
Always cracks me up to hear people talking, who are not FE guys, about FE stuff. They have no clue that other guys build nothing but FE's for a living.