I can tell you that every Ford diesel I have run I have no been impressed with. Maybe with a programmer and some work it wakes them up, but stock vs stock other brands...
When I was in the Air Force we had a fleet of 96-2002 Dodges and Fords. The first time I ran a Ford (been running a Dodge for a while, as we had "assigned" trucks) I thought the park brake was stuck on... yeah.. that bad! I was pulling 2 loaded trailers with bombs up a hill and I started to smelling bad hot, burning smell. Then just about every light on the dash lit up and the truck quit.
We had to pull about 20 loads on that hill over that week. We ended up killing 3 more F350s (burned up the engines!) until the motor pool told us we weren't allowed to use the Fords to pull, had to use Dodges. The Dodges pulled it no trouble.
Trucks looked like this:
At the shop we have a 1990 F-Super Duty (basically a 450 before there was a 450) with a 7.3L, A 2002? F350 crew cab with the 7.3L, 97 F350 with 7.3, 2005? F550 crew cab with the 6.0L and a 2007 F450 with the 6.0L (don't quote me on the years of the ? ones, I might be off a little).
I have run all of them and none have impressed me at all.
I have also run a several Duramax trucks and have owned several Cummins trucks.
The Fords... stand on it... .wait... wait... wait... wait... starts making a ton of noise... wait... wait... wait... oh... ok... starting to go. The 1990 isn't horrible being it's an old design, 185hp, but the others have no excuse. The F450 is a 6 speed, I figured that would pull real nice, but with a cord of wood (barely putting the trucks on the overloads) I could no joke win in a drag race with my 1983 Chevy C350 with a 160hp 350 and 4 speed.
Cliff Notes:
I'm not trying to badmouth any brand of truck, I truly have no preference to brand as long as it does the job. If I was shopping around, I would see about loading down whatever truck and taking it on the steepest hills you can find before buying it.