I have had it installed for about 6 months now and think it should come standard with all trucks. The benefits of being able to go into low gear but still be able to turn your wheels on concrete are HUGE when you have a large rv or trailer with heavy weight and you need to maneuver it.
Whether you are on an incline or just need finer control of the trailer, it is super nice to have this option and not worry about if youre screwing up the 4x4 system in the front if you need to turn sharply on concrete.
The only negative that I would say, I wired it into my AUX buttons and the unit doesnt give you any real positive confirmation (other than the light on your aux button) whether it is actually engaged or not. The first couple of times using it I was worried it wasnt working until i tried to full lock the steering and moved forward.
They do provide a button you can use if you dont have the aux buttons. According to the manual they do NOT recommend leaving the system on if you are in 2wd so I make sure to shut it off but again, it would be nice if there was some type of sound or something letting you know you turned it on and off.