I bought this after admiring it for a while... It's a lot nicer looking, more modern and clean, then a lot of the other cat trees.  My cat immediately took to it, and it has been her place pretty much ever night since we got it.  The only reason I'm not giving it 5 stars, is that the screw on the first shelf doesn't go flush with the shelf -- it initially appears flush, but the shelf is plush, and when stepped on (or squished), the screw protrudes.  My cat doesn't seem to mind it, but I would still prefer it to be complete hidden for safety.

Pros: Great Value, Multiple Flat Shelves, Easy to Assemble
Cons: Nail isn't flush on the first shelf