Slider for 5th wheel hitch, who uses them?

I had a slider on my 06 F350 and used it a couple of times. The one time I did not think to use it, it was raining and I did not want to get wet, I tapped the front of fiver with corner of truck roof. Luckily a park ranger happened to be waiting for me to back in and seen what I was about to do and hit his siren just as I was hitting the corner of the roof. I have a small spider crack in the fiberglass and dealer said it will be fine, could have been much worse. Its a good piece of insurance on a short bed truck.