mid way through a cross country tour I am wondering if I should have equipped my 5 er with a hitch suspension system. I am wondering what experience other folks have had, what type of systems. work and don't
Generally a hitch upgrade such as the Trail Air replaces a portion of the trailer's existing hitch. Typically an extended pin box mounts to a fixed set of brackets on the trailer's nose. The extended box gets replaced with the Trail Air or similar brand. There are several common designs for pin boxes, as shown on the Trail Air site.
I helped one guy install his Trail Air and talked to another owner. Both are very happy with the results, claiming it reduces the fore-and-aft pitching motion you encounter on some road surfaces (e.g. "rumble" strips), RR crossings, etc. Of course, everybody tends to praise things they just spent $$$ on.
As for my experience, I had a rig with and without the TrailAir pinbox and I can definitely state that there is a big improvement in the ride. I've never had an air receiver hitch because they were way too expensive for me. You can always go with the pinbox and then, if it's not enough for you, go to a hitch. You would have no problem selling the TrailAir pinbox.
Oh, I forgot to mention that there are different TrailAir pinboxes so that you should find one to match the extended. Check out their website for details or call them with the make/model of your present pinbox and they'll tell you what they have to replace it or if they don't have one. They are straight shooters there.