I've had both and currently have Chevy 2500 w/ 6.0.  Strong engine and I like that I can reach into the bed, but that comes with less ground clearance.  More car like in the interior which my wife likes.  10-12 mpg no matter what I do.

If I was to buy new it would be a tough call but would lean towards the Ford again.  It seemed heavier built=more solid. 5.4 in one, 6.0 diesel in another.  Wish the gasser had more punch but did everything I needed it to.

I'm not brand loyal and would like to combine things from both.  A lot of opinions and preferences play into the answers you get.  Plus the ignorant brand wars.