Ive raised a couple batches of cots but ive always used a big rubbermaid container with pine shavings or sand in the bottom. I have a large 2x3 pen with 1/2 hardware cloth all around. I know their little feet will fall through so i lined the bottom with that rubber drawer liner. My thinking is instead of having to buy shavings which i hate or sand which works better but cost money i could take this liner out clean it put it back in. Has anyone tried this method and if so how did the food work out i know they love scraching and slinging their food maybe set it over a box to catch the mess or just stick to the solid bottom containers with sand.