Ported GT-40x heads vs AFR185

[hi-tech cobra]

I need help with head selection.

I have a set of ported gt-40x heads with the Ford Racing GT40 VALVE TRAIN KIT for my 347.

I'm concerned the heads will limit what the engine is capable of. The local machine shop thinks my concerns are overblown. They don't think I will gain much with the AFR 185's, they say ported gt-40's with the smaller valves (1.94" Intake and 1.54" exhaust) will actually give more bottom end grunt. But I can't get the AFR185's out of my head.

Here are the specs for the bottom end:
*forged Eagle stroker crank (internal balance)
*forged Eagle H-beam rods
*block: stock roller 302 with beefier after market main caps and girdle
*Intake: Edelbrock Air Gap
*Cam: not selected yet
*Carb: Holley 650 but thinking I need a 750 DP
*Rockers: Comp Cam Magnum's with stud conversion and guideplates

The heads were ported by a nascar head 'guru' in Charlotte, NC, don't have any flow data. Rough guesstimate, around 270 cfm on intake side and 190 cfm on the exhaust. Will the Ford Racing valve train (single springs w/ internal damper) hold up with a high lift cam (aprox .550)?

Any thoughts? Money is tight on this project but I can swing the AFR's if they will make a noticeable impact on HP and torque.
Thanks!