None, but what good does the F-35 provide when the unit price of them far exceeds any and all unit price projections of the Navy and Marines. So according to your logic, the project could be 20 years behind schedule, tens of billions in the hole, and have unit price costs so exorbitant that they become unattainable and definately not cost-effective....but still buy them, because the Navy and Marines have no other alternative, huh?
Your knee jerk solution is fecal in nature.