My cats LOVE this and curl up in a cute ball on the top portion. My cats are 15-20 lbs. I haven’t seen them go inside the cubbies, might be too small for them. My only complaint - it smelled awful (strong chemical) smell when I first opened the box. I let it sit in another room for a few days to air out. Also, be cautious of the shipping. FedEx left the box on the curb instead of bringing it into my apt building’s package room. Not sure why they left it on curb, but I’m thankful no one stole the package.