It only took me about an hour to put the cage together, by myself (and I am NOT a handyman/fix-it type person.... I call for reinforcements when I need to hang something on the wall!)
I have 2 rats in it, and they seem to like it just fine.  There's lots of room for toys - things that sit on the shelves, as well as hanging toys.  The four doors basically allows the whole front side to be open, which makes it really easy to clean or rearrange, or interact with my rats.  
Another thing I like is that it includes a hook to hold the ramp between the levels - so I can put the rats in the top and clean the bottom, or vice versa.  Or if I need to separate them, I can put one in the top and one in the bottom.  
I really have no complaints about the cage.  Yes, it is more expensive than others, but it's huge, it's versatile, and I would absolutely recommend it.