I think it's a stretch to call the "bump" a safety defect. Good grief. But since you don't own a HA and towed with one only once for all of
three miles, I wouldn't expect you to have an informed opinion about this.
As Lantley has said here and in other threads, he used his HA with his exhaust brake with no issues. Slowing the truck does NOT mean the trailer bumps it. Slowing the truck quickly will allow the trailer to bump it IF the trailer brake controller is not set properly. Losing your trailer brakes will cause a problem with any hitch, since the truck brakes are only rated to stop the GVWR of the truck.
The downside of the bump IMO is a small trade-off for the rock-solid towing stability that the 4-bar linkage design that the HA and P3 offer. Once you get the hitch and brake controller set up properly it's a non-issue.
Of course, I run LT tires on my trailer, so I am living on the edge anyway...:B
