Don't worry, though Castrol Syntec is considered overpriced by some it's still a fine oil and will service you just fine for the 4,000+ miles you plan on using it. If you are going to stick with ~4,000 mile OCI's then you might as well use Motorcraft or any Conoco family oil, Havoline/Chevron, Castrol Blend or really any other 5W-20 that meets Ford's spec's for the SM rated 5W-20 oils. Though I will have to admit that Valoline All Climate 5W-20 might not be your bet bet if you want to go over 3,000 mile OCI's.
Whimsey