Any Need To Worry About This Size Fuel/Tool Box In Bed?

Northern Tool has all RDS boxes on sale with $100 off right now. Think I'm going to do it. But which one.... leaning towards the one with the deeper tool box that will stick above the bed rails a little. Seen way too many pictures posted of people with cross bed tool boxes or folding bed covers stacked at the back and then a fithwheel hitch in the bed. Must not be as big a problem as some have said. Besides it could be in a couple months or it could be years before I get that dream toy hauler.