In a household with 10 indoor cats, we purchased one tree, and because the quality & price are good, we bought a second.  Our felines hang out in different  "groups", so they gravitate to one tree or the other. (they are in separate area of the house).  The only feature I didn't care for is the fleece which seems a bit thin.  However, the hardware is superior to a previos brand we owned.  Stability is fine.