I'd also recommend using fleece as bedding. Soft, warm, absorbent... The problems with particulate matter (like shavings, carefresh, etc...) is it can be dusty and has a tendency to travel all over the house. And, since there are all those pieces, it tends to hide poops, pee, and blood. Fleece helps you detect changes in potty habits and noticing blood.
Paper towels are great for the litter bin. But not good for the whole cage.