371 build W/Big Mouth heads

Are you sure on the flow numbers.... MIKE at MRL is freshening up a stroker with big mouths and i asked what they flowed and i recall he said 314-315??? i guess i should of asked if he had them on a flow bench ....
Very strange that most builders can achieve 300 on a stage 3 cnc port job ...out of eddies ... who do you believe ?