I am sure this one has been discussed at length, just adding my recent experience. I have spent about 3 hours researching this topic and the conclusions are pretty varied.
I just bought a 2026 3100 RL. It is equipped with the Curt Helux pin box, and I was planning to use it with an Andersen Ultimate (newest gen). I called Andersen yesterday to discuss the combination. They informed me that it works fine, however due to the forward tilt of the Helux pin when not under load, hitching and unhitching MAY be problematic. They recommend the use of a lockout (basically a shim) they sell to keep the helux level when hitching.
Received a call from the Montana Dealer (prepping the trailer) today informing me that the 5 year structure warranty would be voided if I use the Andersen according to Keystone/Lippert as it places undue stress on the frame of the coach.
Long story short - I am swapping the pin box from a Curt Helux to a Curt Gooseneck. This gives me a few advantages

Moral of the story - had I known this ahead of time, I would have negotiated a large discount on the pinbox swap from the dealer.
Winz
I just bought a 2026 3100 RL. It is equipped with the Curt Helux pin box, and I was planning to use it with an Andersen Ultimate (newest gen). I called Andersen yesterday to discuss the combination. They informed me that it works fine, however due to the forward tilt of the Helux pin when not under load, hitching and unhitching MAY be problematic. They recommend the use of a lockout (basically a shim) they sell to keep the helux level when hitching.
Received a call from the Montana Dealer (prepping the trailer) today informing me that the 5 year structure warranty would be voided if I use the Andersen according to Keystone/Lippert as it places undue stress on the frame of the coach.
Long story short - I am swapping the pin box from a Curt Helux to a Curt Gooseneck. This gives me a few advantages
- This approach is "factory approved" if using Curt or Reese gooseneck pin box and the frame warranty stays intact
- While the gooseneck is ~30lb heavier than the helux pinbox, the fact that I don't need the Anderson actually saves me 10lbs payload
- The bed is basically clean when I unhitch, albeit removing/storing the Andersen is pretty straight forward
Moral of the story - had I known this ahead of time, I would have negotiated a large discount on the pinbox swap from the dealer.
Winz

