I have a 2012 2500HD crew cab 6.5 ft bed
I have a slider hitch, never used it. should have once.
In most cases I don't need the slider. I had a 2006 and now a 2012 5er that were both fairly rounded in front. Not a problem.
There was one instance that I wanted the 5er in a spot that had no room in front of it. My truck was at a 90 degree angle to drop it off. when I went to hook up I must have been 91 degrees. RV just barely touched the cab and the back window popped. but in 8 years of pulling 5er's, never needed it for a campground or my drive.