I've been using the ursack (large) for about 3-4yrs, and always use it except in areas where a canister is required.
I always securely fasten it to a tree, about 5' up, so a bear can't leverage his weight.
I love it and can pack 10days in it.
I don't use a liner to prevent odors.
we only hear the stories of where a bear managed to get it off a tree, where maybe they weren't tied on properly, who knows...and either crushed or rolled or carried it away, but we will never hear the stories of the ten thousand times it worked well.
you can also hear stories about the same kind of things happening to a canister.
I'd be more worried about a critter wondering into your camp during meals or before you've hung the bag
Last summer in the Teton Wilderness, 2 moose (meeses?😁) walked into camp during breakfast, I was the only one to quickly snatch up all my food, stuff the ursack and tie it to a tree, probably unnecessary, but I wasn't taking any chances.