Okay my opinion may be a little biased here, but...
I would never own a 6.0 PSD. They just have too many notorious problems for my taste. Sure, with lots of work you can have a reliable truck, but the idea of band aiding a motor prone to failure doesn't seem like a good idea. I do apologize to the Ford guys about my rather "harsh" opinion of the 6.0, but I don't see the reason when there's a perfectly good Cummins sitting under the hood of a Dodge.
As far as the Duramax goes, they also are plagued with injector / IP failure and VERY poor fuel economy. I have talked to more than a few people that are Dmax owners (mostly of 05s, the LLY, supposedly best year) that couldn't get over 13 mpg empty! A scary thought...
And this leaves Dodge. Now, there are plenty of Dodge haters out there, that say the truck falls apart around the Cummins. This is the case with more than a few trucks, but get one that hasn't been super abused and its fit and finish is great (in my opinion). My personal rig is a 97 with over 300k on it, and it is by no means falling apart. There is a reason that all the long hauler guys that haul vehicles or travel trailers drive a Dodge. My personal favorite is the P-pumped 12 valve. These motors are damn near indestructible. I worked on one of these trucks that had over 200k which was running the original oil filter, fuel filter, air filter, valve adjustment, etc. The motor still ran great but was a little down on power (imagine that!) and after some maintenance it woke right back up and now has another 100k on it, trouble free. The 2nd gen dodge in particular is an excellent rig. They can be had from between 4k-12k, and the NV4500 is a great trans. Admittedly the 47RH and RE are slushy pieces of trash, but if you don't mind shifting your own gears (and I know most of you dont) then you've got an excellent rig. Sure the front ends are junk, but there are companies like Moog that make parts with lifetime warranties. And sure, the paint and the dash leaves something to be desired, but the rest of the truck leaves me very few complaints. These trucks are by no means rare and parts are always easy to come by and generally inexpensive (however the Dodge stealership is very proud of their parts) and there is tons of aftermarket backing and a HUGE knowledge base online. Not to mention, these motors can make excellent power and still be reliable and fuel efficient. Heck, I routinely get over 20MPG on a 4x4 7000+ pound truck. You just cant beat that. :sombrero: