I had my early 99 f250 that was done up right and went like a bat out of hell, bought a new fifth wheel and the weight forced me to upgrade. I got a 2014 f350 6.7 platinum (which I didn't want to get as my old truck towed the new 5th beautifully but I was 300lbs over my gvw with no passengers)
now I would never go back, I had DP custom tuning, injectors and countless other mods and the new 6.7 is dead quiet, out tows it hands down, rides better, and gets better mileage. Oh and did I mention it is quiet? ;)
Steve