I have seen 100s of the GM vans\trucks with 300k miles on them, purchased by private companies, and still run fine. One guy I know has several Chevy trucks with 400k on them. ( he is cheap) Ford likes to tout the F 150 being the best selling truck around, but that is assuming the sierra and silverado is a different truck, put those two together.............for a couple private companies I have worked for, GM trucks and vans we used extensively, with little issues and minimal maintainence.
Sure the Nissan has more room, but how many do you see driving around.......I suggest next time you are out and about, look and see what most private companies have as their vehicles...........and the reason why i say private companies..................they are not all about the bottom line.............and rely on their trucks, whereas LARGE companies get special pricing on fleets and are about the bottom line..........
Disclaimer, i am a chevy truck guy, but not because any other reason than personal experience and observation.