I was never an oil burner guy until I bought one in 2020. It's wonderful to have effortless power towing the camper, set the cruise and drive. No more monitoring momentum and hills. I guess I have been "lucky", both this truck and my last truck have been perfectly reliable. Most of them probably are, whatever brand. I will say I have never felt like I needed more exhaust brake and unless you are towing way heavier than 10K, it's a non issue.
So to me it comes down to what do you want to spend your money on? It will never balance out on pure need. Of course that is probably true of most of the things we buy for ourselves. I'm pretty sure I don't NEED this Ultimate, but it sure is nice and I am not getting any younger!