A lot of places use woodchip flooring for Apes/Monkeys nowadays. I think its probably beneficial both for enrichment and warmth and maybe helps prevent wear/abrasion of the animals' coats too. I can't see any real downside apart from maybe too dusty if it gets too dry?
The interior of the Orangutan 'forest' is perfectly okay- quite typical for a modern Orangutan design.
When I saw this sort of flooring in Apenheul, it looked much more 'composty' and worn, but maybe it had been down for some time. This looks a bit more like the woodchip recently laid down in Paignton's ape house - a bit new and spikey.
