I currently use sand (on top of linoleum) and I love it. It is so easy to clean and doesn't smell. With our cold winters (it's already been getting down into the upper 20's at night) I plan to take the sand out of the coop and put it in the run. Then I'll put several inches of pine shavings in the coop for the winter and add as needed. Next spring I plan to get more sand for the coop.