Op, the CP3 pump used in the Cummins is much more reliable than the CP4 unit used in the Ford and until this year, the GM diesel offerings. When the CP4 fails it sends metal shards throughout the entire fuel system trashing every component. When the CP3 fails, the truck simply will not run.
Don't let people try to convince you that these CP4 failures do not occur; they certainly do and you are most likely left holding the bag for the cost of the repair, especially if the truck is a Ford. I have seen 2 recent reports in the consumer section of our local news of VW owners in the same position (their diesel cars use the same pump).
I was a die hard Ford man for over 20 years and ended up owning a 6.0L diesel. When I finally had enough I looked into the 6.7L Ford but just could not do it and have to add who knows how many aftermarket kits to take care of the engine's shortcomings. If you look under the hood of a 6.7L Ford you will see that they are extremely complicated and will cost a fortune to repair. If you only will have the truck for the warranty period they would be an awesome truck. I intend on keeping my truck for a very long time so long term reliability and repair costs were paramount to me. I bought the truck in my signature 3 1/2 years ago and couldn't be happier.
The current thread about the Shell Rotella oil is about the Ford 6.7L engine. Cummins has not issued such warnings about oils. I'll leave the rest of the puzzle to you. ;)