Personally, I wouldn't. Just because, as Abnoba said, I'm not sure if it's safe to be eaten.
I do use fleece, though, and that's been really good.
Just a layer of fleece (the absorbant kind) at the bottom of the cage, with a couple of layers of towels underneath. Sweep out the poos every day, and stick it all in the washer two or three times a week.
It looks tidier, they smell less, no mess being kicked out all over the floor, it's cheaper, and my boys absoloutely love it!