I am so thrilled with my PetSafe-self cleaning litter box.  It is fantastic-I cannot believe that I haven't gotten one sooner.  It is really easy to set up and it is very sturdy.  I was worried that my cat would not like it, but she started using it right away.  The tall sides keep the crystals in the box and there is no odor at all.  The self cleaning feature is very quiet.  I love that there is an indicator for how many times it cleans.  I know my cat is using it.  I think the only (minor) downside is that it is pretty big.  I had to re-think my littler box space.  Other than that it is great.