I own a 2004.5 Dodge RAM with the 5.9 325hp engine. I recently sprung for new injectors due to symptoms of worn injectors (some smoke). Bought brand new, non-remans, from injectorsdirect.com for $2k.
Take a wild guess how much it costs in labor to replace those injectors at any standard diesel shop ... ?
It cost me less than $500! Guess how long it takes an experienced mechanic to replace the injectors and crossover tubes on a 5.9? Three hours, and that includes beer breaks! Book is 4 hours.
Compare that to the Ford, or Duramax. The injectors aren't going to be much more (8 vs 6) but the labor costs, especially for the Ford, is insane. For some mechanical work on a Ford 6.0, the cab has to be lifted off, and put back on afterwards - book is on the order of 20 hours just for cab work alone!!
IMO, it's stupid to buy a Ford unless you own it only during Warranty.
As for the other poster suggesting to buy a Hemi. It may be true that at stock levels, the Hemi is comparable to the Cummins but that's only until you wake the cummins up by removing the "air before fuel" requirement using even the least expensive (Superchips 3805 $100) programmers - whereupon one can see immediately that the Hemi is a slow and much to weak for the truck and any substantial added weight.
Just food for thought. Cumminsforum.com is a great resource for Cummins owners.