My cat  loves this!! He is a big cat and just fits in the opening and he doesn't care that a paw is outside. He climbs on the top tier and sometimes pats me on the head as I pass. Its strong enough so it doesn't tip . Its butted up against a wall and when it does tip it falls against another wall. He's learned to balance it I guess. Its soft and he can scratch it and rub his face in the soft fur.