Well some thoughts, the 6.0 can be a great engine, you just need to get a good enough deal that you can take the savings and invest in having the engine "Bullet Proofed"! You will still need to be 100% on target on maintenance, I have heard that Ford now recommends a 3,000 to 5,000 oil change interval, my Cummins goes 10,000 on dino oil just fine.
The other option is to look out side your area for a Dmax or Ram, I have always found it interesting that Ford and GM felt a need to re-brand their diesel engine choice, Dodge/Ram felt proud to rum with the Cummins logo.
FYI, I was a True Blue driver all Fords except my first car (VW), and I would not buy a 6.0.