Hubby says we need more power!!

Welll, I have had a number of Motorhomes of different sizes and weights. THey number 6 in total so that lets me have a wide range of experiences. FIrst motorhome was a 34 foot Foretravel with a 350 ISC and Allison 3066R transmission. It would run up the mountains at about 2100 rpm and about 50 mph. I move to a 36 foot Foretravel with an ISM 450 and an Allison 4000R and went up the same mountain at 55 mph and then moved to a double slide 42 foot Foretravel with the same set up and took the same mountain at 45 mph. I had two born free coaches with he V10 one 24 and one 22 foot. I took it at the speed limit with the engine screaming and now in a Born Free on an F550 with the 6.7 Powerstroke on a 29 foot coach at 70 mph and no real increase in noise and only dropped down one gear. It is about gearing and weight to Torque and HP and how much gets to the ground. I have been passed on a big hill by a Prevost but not much else when I was in my Foretravel but now I can climb anything with ease. That said it is not a race to the top but it is getting to the desitination and all of them got me. I would not upgrade for more power but for what the coach offered. I went from 34 to 36 to 42 and and from 22 tho 24 and now to 29 to get out of the over head bunk or I would have kept that. I downsized by selling the class A too. It works for us and I never worry about how long it takes as long as it is climbing at a reasonable rate.