6.4L Hemi tow report - weights added

I have a comparable sized 5th wheel. I am looking at going to a 4th gen Ram, and I have read both of your larger threads on the new truck. I am still deciding between 6.4 and Cummins. Drove both a couple miles yesterday and was impressed with the low end in the 6.4.

Obviously it is handling the trailer well, but any regrets so far? Missing the diesel when you were climbing the grades? How steep were the grades when you had to drop to 2nd?

Thanks