I still have the stock inlet and my tuner loves the stocker. I make 710 rwhp. I actually want to buy another stocker just to have. Keep in stock. Stocker is good.
The engine builder a mustang magic told me the gains are made once you go with bigger piping, bigger maf and the inlet. Just what was mentioned above
I would keep the stocker too, but it just doesn't fit over the BBK 65mm throttle body.