For me it was primary down to the ride on an NP300 being far better than any other pickup on the market that I had experienced. On paper its also the most economical.
Coupled with the fact it was about the cheapest vehicle on a high mileage lease deal it made the most sense. Although an L200 was cheaper it was not as nice to drive but I do somewhat feel that the L200 might have made a better motorway cruiser with its wider spacer ratios.