The lead truck technician at my local mega Ford Dealer told me the 3.5 EB is problems and the 5.0 is a better engine and that's the main reason why I picked the 5.0.
I have the FX4 and the option for the 3.5 EB is much less expensive than the other F-150 models and I still went with the 5.0 even when everybody else said I was crazy or I own the ONLY FX4 with the 5.0