The ladder looks natural, my chinchillas literally jumped on it and have been gnawing at it like beavers for 10 minutes :) Plus, they're having some fun with it. It's well made and cheap.
I have two little rats and ever since I gave them this, they've loved it—chewing on the straw, the sticks, even the little balls. They tore it up so much that I'm going to buy four more so they've got plenty to spare.