I think it dont matter what you use . They love to scratch it back out. LOL How tall is the front of your nesting box ? Mine is 3 in. and not tall enough.
My 20 week olds are shoving straw out right & left, checking out the boxes. That usually calms down some as they get older if you have a lip (3 inch?) on the front. There are plastic mats that you can use by themselves to cushion the eggs. Just search for next box pads!
I have 6 nest boxes and I've been experimenting with using front-cut-out plastic tubs with pine shavings placed in the boxes and also bought some nest box liners made of excelsior. The experiment is to see if the hens have a preference, which so far I have not noticed any preference, but regardless of the box lining, they still dig it up and throw it out. Even the excelsior that is glued to parchment paper has been dug up and some of it thrown out although not as much as the pine shavings.
Other observation is that on several occasions, I've seen a hen laying in a cut out tub and there was very few shavings left in it and they still laid an egg on the bare bottom of the tub.
While I always put more shavings back in the tubs and they again dig them out, apparently it is not a requirement of the hens to have the shavings to sit on. If it was, I would expect them to avoid the tub if it is bare.
Bottom line, hens will do what they want to do so I just let them dig and throw shavings where ever...as long as they keep laying those beautiful eggs!
Mature birds tend to be less destructive than young, new layers. An active kicker will knock any type of bedding out. A deep lip holds bedding in place while the bird makes her nest. Can you show us your nests?