It would be the truck I wanted. No matter what the mileage or year model. When you see it, you'll know. Forgive me, but I don't remember though, does the '08 2500 6.0 have an Allison transmission? I would tend to go with a truck that has a transmission that is not likely problematic down the road. I just can't remember if it does or not. That being said, if something were to happen to the tranny, they can be built to handle any of your towing needs if it were to come to that. Now back to your question. It boils down to what you want. If you want a newer truck with all of the bells and whistles, you'll most likely find them with higher mileage for the same money. My first dually, which I still have, was a base Chevy 3500 8.1L CC DRW 4x4. No power anything, but had a/c! It still serves its purpose well, just may need a little work now and then, but it does what I want it to do. That may be true for the older trucks. But at an '08 year model, I don't think a lot has changed. You should be able to get a fantastic truck in any model since then. Good luck in your decision. Get the one you want and are comfortable with, whether it be sacrificing miles or bell and whistles.