If you want to get into more detail, the Dana 60 is one of the more efficient rear ends, even more than an 8 3/4", while the Ford is one of the worst. It's a small percentage, but it is there.
It has to do with how close the pinion is to the ring gear centerline. Plus, the Ford has an extra bearing - more drag.
If you know the gear you'll be staying with, go Dana 60.
This
...I am currently in the same dilemma, I will probably go with a 9" Ford simply due to the ability to change 3rd members as necessary.
