My 3 cats absolutely love this!!  I often find one on the top perch, one in the basket-their favorite spot!, and one in the house perch.  Lots of sisal to help keep them scratching where they should be.  Don't use the hammock yet, i don't think they're so sure about it-but they love the basket.  So i put all the toys etc in the hammock.  Actually, i think they just don't care much about it because it's on the bottom.  There are much better places to be!  It is big, but that's why i got it.  Fits great in the corner of our living room.  My cats are smaller, about a year old.  We have one other cat that is huge, he wouldn't like it probably because he can't fit anywhere on it.  It's for average sized cats i'd say - remember they love small spaces!  I've already recommended this site to a bunch of others, and my mom bought one the other day that she loves too!