I had a 2007 Duramax 2500 SLT 2wd with 165k and sold it when I found a 2012 Ram 3500 LongHorn Laramie with 45000k.
I wanted the 1ton rather than the 3/4 ton and the 4x4.
I had a lot of reservations about selling my Duramax as it was a great tow vehicle and zero problems. The duramax got better mileage when not towing because of the dpf on the Ram , but when towing they are the same. The luxury features of the Ram LongHorn are great and I have no regrets on doing the upgrade.
When I did the change I also drove a 2013 Duramax with similar mileage but the Ram was far and away the nicer handling vehicle in my mind.
As mentioned " no regrets " I'm a happy camper .