I have a retired F-350 SRW that I used to pull a 39 foot toyhauler. It's retired from pulling my RV but it still works on the farm. I was never happy with the stability of the truck in turns, the back end always seemed to soft in the suspension and tires. The braking capacity of the truck was no where near adequate when my trailer brakes failed. That event alone started my search for a new truck.
Being in the automotive industry and a hobbyist in aviation, I wanted to find a truck that far exceeded my trailer capacity in gross weight and stopping ability. Applying some of the aviation systems mindset "redundancy", I wanted not only the primary braking system (truck plus trailer brakes), I wanted a truck that had enough weight, stability and braking capacity to stop the rig in the event of trailer brake failure. The Freightliner M2-112 does that.
This is only my opinion and my comfort zone. Many have commented that I went too far in my truck choice. I'm not sure I understand what "too far or too much truck" means. In my mind, it's far better to have too much truck than too much trailer.