I just checked and the center of pin on the new hitch to back of cab on my truck is 39.5". The pivot arms on the hitch are installed towards the rear of the truck which clearly makes a difference. I never measured with the Curt, but I'm pretty sure this B&W provides more clearance to the cab.
My trailer is currently in indoor winter storage so it will be another month or so before I have the chance to hook it up and check things out. The trailer is a 100" wide body so definitely wider than many of them out there. It appears that I may have been able to get away from a slider, but I'll have to experiment a bit to see how much sharper I can turn before it gets dicey.
With respect to experience, yes it makes a difference, but when you are in a situation where things are tight and you are trying to watch multiple things, it's very easy to forget to watch the cab clearance as I've found out. As I said earlier, I would rather have the insurance of having the slider and not need it than the other way around!