Decent size set up but a bit boring for them, not being funny but all 3 levels are the same, shavings and more shavings..
put a couple of carrier bags in, handles removed to give em something noisy to roll around in, or a small cardboard box with a couple of holes in..
its not only fun for them but it keeps them fit.
I would also put a water bottle on the top level, would you want to walk down 3 flight of stairs to have a drink