I've been using this litter box for about a month now and I'm very impressed with it.  I love the fact that it's trouble free until you need to change out the tray.  With one cat like us, we're still easily on the first tray nearly a month in and we haven't had to touch a thing. 
No odor.  We don't even know it's there!  Just from setting it up, I know that tray change out is very simple and clean.  With my experience, I'd recommend this product to cat owners that either don't like handling and cleaning a litter box on a regular basis OR owners of finicky cats like ours that insist on a constantly clean litter box.  
I think if I had to do it over I'd consider the more advanced model, just because that gives you some feedback on how often your cat is using the box, etc.  But, if that's not important to you, this is a great model. [This review was collected as part of a promotion.]