I bought a Cummins last spring, I love the motor more and more everyday from the sound to the power, at that I do not like the truck.... but I feel the 3rd gen's (03 and up) were made stronger. There is no such thing as a perfect world, if so the ford w/ with the cummins and the ally tranny would be it. With the 6 cyl. the sky is really the limit with power and they get better fuel mileage. I've heard of 20mpg and I've seen it, but thats driving like a baby. The ford 6.0l had bad head stud problems and the Cummins had bad fuel pump problems. You'll be happy with the Cummins but I can't promise anything on the Dodge. Plus the Cummins usually has better resale, and the motor is like a mini semi motor.