For factory extended warranty, go with Flood Ford.
They sell the factory warranties online, for just over cost (they make $ in volume). All the F150 guys buy the warranty from Flood Ford. Purchased on 2 trucks as well. My local Ford dealer covers everything under warranty no problem.
I did give my local dealer the opportunity to price match Flood Ford, but they said their F&I guy wont do it less than $500 over cost, so recommended I get the Flood Ford one. Again, they sell the factory extended warranty, not an aftermarket warranty.