I prefer the car pumps if diesel is available as it is easier then dealing with the big rigs and their doubles at most truck stops. The truck pumps put out the diesel faster which is good but so do the DEF pumps which is not good. On a trip last week we encountered a Shell station that had diesel and DEF at the car pumps and it was great. The DEF was on one side of the bay and the diesel on the other so I could add DEF while my wife added diesel. The DEF pump nozzle was also much smaller than the ones at the truck pumps and lower output rate so a lot less spillage.
Part of my trip planning is locating places that sell diesel so I have places that I know will have it. I use gasbuddy.com and yellowpages.com (search for diesel fuel and nearby the towns along the route). If I find diesel and I am at half a tank I buy it and don't wait for it to get lower. That way I have more options for side trips without worrying about fuel. One does not want to run out of fuel with a diesel engine.
If your vehicle has an option for putting in a large capacity fuel tank I would do it regardless of the cost for the piece of mind and added flexibility.
At least with all the new diesel powered cars being sold it is getting much easier to find diesel at places other than truck stops and in smaller towns further off the interstate highways.