How disappointed will I be

We bought a used diesel truck (Ram) a year and a half ago, to tow our RV. It only gets occasional local use other than towing duty. Even though it now has 145K on it, I have not had to do anything but normal maintenance -- no repairs. Personally, I will never ever go back to towing with a gasser. Just no comparison in towing ease, plus mileage is better with the diesel.

Also, don't know how long it will last, but for quite a while now, diesel is cheaper than gas here, lately over 40 cents a gallon cheaper. Sometime down the road, resale will be higher, and it will sell easier and quicker than a gasser.