Both the Hemi and the 5.0L (i have one in a 2011 Mustang) are great engines. The Hemi has the displacement and power advantage (in truck trim) but is thirstier.
The Ford 6-Speed has an almost 40% lower 1st gear than the Dodge Trans so it doesnt need as much gear. When it works right the Ford Trans is superior in almost every way. On the other hand issues with it seem more common than with Dodge.
The Dodge rides a bit better and doesnt have the vibration issues that Ford has been plagued with since 2004.
I believe the Ford would be a better tower due to chassis and trans despite the smaller engine.
Overall the trucks are close enough that it primarily comes down to personal preference or price. The Dodge can usually be had cheaper.