I love all Modkat products because I use one of their litter box; it's fantastic.
I have a Modkat flipster & because I live in an apartment I chose to stay with paper liners for ease of cleaning & disposal. My favorite litter box for sure in terms of function & style. Most of all, my kitty, Camden approves With the right cleaning & litter, the liner never becomes wet. I throw it out very easy.
We like the inner liner AND the cardboard liners. I have to be very careful when lifting the cardboard liner out every week though so it doesn’t break and dirty litter falls out since my cat only pees in one corner which gets soaked.
I find these easier to use than the plastic liners. Easier to dump the old litter, fold up and put in recycling. My cats don't like plastic liners anyhow. So, please continue to make these!