Well I prefer cypress/coconut husk or paper towels for bedding. Aspen is fine, it's all a matter of taste. Astroturf or repti-carpet (it's essentially the same thing) is alright, though I don't like it personally because you'll always have to have two pieces and switch them out when one is being cleaned, coupled with the fact that they'll harbor germs after a while and they'll have to be thrown out and replaced.
For something easy to clean and that makes no mess, I'd say go for paper towel because that way if there are just a couple segments that are dirty, you remove the dirty segments and replace them with clean ones. It's cheap and easy, although it's not as pretty to look at![]()