I am looking at a F650 for my operation. I know some people like and use this vehicle but am looking for those with experience maintaining these. It has a Cummins engine, 187k in miles and is a 2010. What pitfalls should I be looking for here as I meet with the seller? Any long term maintenance issues I should be aware of? Here are the particulars:

2010 Ford Super Duty F-650 Straight Frame, 325 Horsepower Cummins Diesel, Allison 3000 Auto Trans., Hauler Bed, 300 fuel capacity, air brakes, air suspension, air seat, 2 speed rear, gooseneck, pintle, and receiver hitch.

Is a "straight frame" a positive or negative? Primarily this would be for local and long haul of 100-150 colonies at the most at a time. thanks for your input.