George loves his, one corner is his toilet, the rest of it is his digging and half rolling area. He also uses it as his landing area for his death defying leaps from his hammock
When it was warmer I divided the floor of Dinah's viv and she had half sand and half wood-shavings. During hot weather she burrowed in the sand a lot and slept in her burrow. As the weather got cooler she stopped using the sand at all, covered it over with wood-shavings and just used the wood-shaving side. Today I've given her viv a full clean and removed the dividers and sand and she just has a mixture of wood-shavings and hay. I'll go back to half sand next spring.