If you want to go the gooseneck adapter, may I suggest the Anderson ultimate goose neck adapter. ( I know guys, ready for the slams). I have been using one for over a year now and the more I use it, the more I like it. I cannot see where it adds additional stress to the the trailer as the leverage spot is about the same as a fifth wheel with the exception that it rotates on a ball instead of a pin. I did contact Libbert and they state it will void the warranty, however they would have to prove the hitch caused the problem. Anderson will warranty your trailer if any damage is proved to be caused by the adapter ( I have that in writing). This warranty has never been tested that I know of. More and more dealers are now selling these, and actually recommend them, rated to somewhere around 24,000 pounds.
Flagstaff 8528 ckss fiver
2008 Ford f350 dually 4x4 desiel