Pretty unusual for the head gaskets to go on the 5.4L. It would take major overheating, and it has the "fail-safe" cooling system which makes that really unlikely. Also it would be unlikely that a bad head gasket would only leak eternally.
I think a 2nd opinion is warranted, and also suspect it's probably dried out valve-cover gaskets. Also the PCV hose can crack and cause oil to spray everywhere.
And speaking of the PCV valve.... major oil leaks are often caused by a sticking PVC valve, especially valve cover leaks. Mine stuck completely, blew oil through the oil-cooler o-rings until the coolant reservoir got full, then it ruptured the heater hose and blew the PVC valve right out of the valve cover at the same time. I though for sure the motor blew! It was a huge mess! It rattled when I had last checked it 100,000 miles before, so I stuck it back in to save $3. Not worth it.
