Had travel trailers pulling with gassers, hated them. Bought a fiver and went with diesel truck, never went back to gasser. Night and day difference. As another poster mentioned the exhaust brake ... Absolutely great feature in a diesel.
We now have a DP MH and don't travel three months a year ( maybe one) but to us it's worth every penny, also better resale than a gasser. It's quiet ... something you won't get with a gasser. If that means something to you in making your trip more pleasurable rather then possibly having to wear wearing ear plugs, then it's a plus in my book.
I was getting 9.9 mpg on our 42' with a toad on our last trip, engine isn't even broken in yet. It is a great ride with a DP and no worries going up or down the hills. I practically don't have to use brakes much ( except full stops or hard stops) as the exhaust brake is that good. So you probably save a lot of money in other maintenance area's over a gasser ( oil changes are more). The better ride is worth the extra costs "if any" over gasser. Most of it is just changing a filter for the air drier every few years, or pulling a few lanyards to release air from the tanks every 6 months (lanyards - very simple - you can do it). Other than that it's not much more then what what the gasser is.
Who cares who gets to the top of the hill faster, I never understand that as a point to discuss anyway. IMHO either one will do the trick. If money is the issue - gasser - if not diesel. Honestly, in the long run your better off with the diesel in more ways then one. Your buttocks and ears and piece of mind will be appreciative of your diesel decision.
