Are you seeking responses from people who have installed these and have personal experience with the specific product?
My guess is that this part is indeed an improvement on the factory part. Hellwig's part description states "Hellwig sway bars feature larger than stock diameters and precision engineered components to optimize handling and reduce body roll."
I have not used this specific product, nor have I upgraded my factory sway bar on the '17 Expy BUT, it is definitely thicker than my stock part (photo attached) AND I can speak from experience in having upgraded several sway bars on multiple personal vehicles over the years where they all exhibited significant improved handling.
With that said, I do know there will be several variables to take into account which are going to be unique to your application: how much weight are you pulling? How much tongue/hitch weight? What percentage of the factory max towing capacity are you using? How many axles does your trailer have? What type of hitch setup are you using? Are you using sway control?
Answering these questions will help in your decision making process, but hopefully others will chime in who have experienced with the Hellwig upgrade.
I'm also curious to follow your research on this topic. I've been on the fence with this bolt-on for a couple months now.
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