Do your homework before putting after market running boards on. Infiniti might just come out with them as Nissan starts pumping out the new Pathfinder.
Our 2010 Armada had them and they were good and wide. I did have to watch my step because sometimes while exiting the vehicle I would miss the and hit the ground ackward. We drove the latest QX (loaner) for 7 weeks and it too had running boards. They were narrow and with my size 14 feet, I slipped and hit my shin bone several times.
If you find after market running boards, please post pictures and all the scoop.