Always love these threads... so many opinions.
I've owned all three makes. I've got no use for Dodge; the trucks tend to fall apart around the motor. Had good luck with the Duramax's overall.
In respect to the OP's question, I currently still have 4 trucks with the 6.0. We have good return on these, but they like to be ran hard. Driving around an RV once in while and going to work or getting bark once a month isn't going to cut it.
Two of these have had the studs done. It seems to be a given and I'm ok with it. Still cheaper than a new 6.7.
I've got no problem with the engine. It's a matter of where you're going to spend money. New payment (most folks) or a repair bill... the ROI for us is still there.
The biggest issue for me is the age of the truck over all (running gear, etc). The 6.0's are getting to the age where I hesitate...the truck has to be in pretty decent condition.