I had a '19 Legacy and never use the lane assist because it was really aggressive and overcorrected too much when trying to stay centered. Even on highways.
I now have a '21 Tour XT and I have to say I love it compared to the '19. I use it extensively on highways and even on some highways that have plenty of turns it works well for me. Now I have the Cruise Control setting to "Dynamic" so I don't know if that matters.
I will say that my wife has a '21 Ascent and hers is as bad as my '19 Legacy. I can only use hers on highways that are pretty straight. When trying it on one that goes through mountains/hills it's too "bouncy" to use comfortably.
