I have thoroughly tested my F150 2.7L, our Silverado 5.3L and my RAM 5.7L. My Ecoboost was without a doubt the fastest truck we owned, whether 0-60 or 1/4 mile. Not sure about top speed.
The only way I can see a Hemi beating a Ecoboost is purely as a driver's race scenario, especially if the Ecoboost is 2wd. Due to the low torque curve & near instant torque, it's easy to spin the tires on a 2wd truck and lose all your time there. In 4H, I would be surprised if even the 6.2L GM could out-drag the 2.7L Eco.
I also love my RAM Hemi, I can live with it being slower than my F150