I spent a ridiculous amount of time going over cat trees before choosing this one.  I recognized that most complaints had to do with the levels being too small for grown cats, and really that was true to form when the tree arrived.  Husband put it together in about 30 minutes and overall I was pleased with the quality.  We put it in a corner to help with stability and then put some bricks around the bottom.  Our cat loves cubbies so he hopped in this one immediately but was displeased with the lack of space.  There are two posts in the cubby that make it even smaller and we're pondering ways to re-engineer it.  I should probably have paid more to get something sturdier and larger but I just couldn't stomach it.  This one will probably be fine for now unless he topples it and never wants to use it again.