i have 3 of these now, absolutely love it and so do all the cats. the half circles are good enough sized for my 8-11 pound guys, and the top is the best- even my really big guy (15+ lbs) can sleep and be perched up top, real stable too. Only thing is one of the 3 had like a shag carpet on it -the others a shorter pile- and the shag pulls out really fast and easy when they climb or scratch- so i just bought some sisal rope and covered the other posts to cover the lack of carpet etc. Still even with that issue- the pile ones are great and love the size and sturdiness of it all- also comes assembled and the cats really really enjoy them.