I actually use a mixture... I put a couple layers of newspaper down, then cover that in a layer or two of paper towels. The paper towels soak up any liquids fairly well, while the newspaper just covers the bottom for solids. Easy to clean too... reach in, pull it up, scrub her down, put new in.

I also used carefresh for a while. It worked well until she got it all packed down. Spot cleaning was easy, but cleaning it out entirely was a pain the rear.

I've had my six foot girl for about four years now, and have never had a problem with her impacting on anything. I guess if she got a huge mouthful it might be a problem, but she's always spit out anything that wasn't food (best she could anyway) and any remaining pieces would be small enough to pass right through her big boa body.

Just my experience