Every once in awhile I find something I must share with you - simply for entertainment purposes. This is an Amazon customer review (1 Star) for the Scoop Free Self Cleaning Litter Box. And, no, we do not have cats, are not in the market for cats, and to explain how I came about this is way too complicated to bore you with.
These are poor Matt's thoughts on this product.
Maybe I'm just doing something wrong, but honestly, I can't understand all the rave reviews. I have a 4-month-old kitten and I am well aware that kittens will use up litter much faster than adult cats, but we're still talking ONE CAT and I am only on day 5 of a fresh cartridge and the smell is already so intolerable that I can't be within 5 feet of the box without retching. It literally smells like someone peed in a leather boot filled with oatmeal and then microwaved it for 15 minutes. Anyone that says they manage with one cartridge for 30 days is either a liar, criminally insane or lost their sense of smell in some freak, manure-huffing accident. To contrast, I had no odor problems with the scooping litter I was originally using (I'm talking a post-poopfest, pre-scoop, completely-thrashed litter box too). Also, even with the hood and the carpet (yes - I'm the sucker that bought all the accessories), the crystals get EVERYWHERE. Then there's the price of the refills. $51.99 for three, or $99.99 for six. The audacity to charge over 15 dollars for a piece of cardboard and a pound of litter is breathtakingly criminal, and that's even if they lasted as long as the company advertises. I bought a 3-pack of litter cartridges. With these, along with the one that comes with the box, I thought I would be set for 4 months of scoop-free bliss... how sorely mistaken I was. I am already on the third cartridge and I'm already about to toss it and pop in the last one.
On to the rake system: I will admit that it's a rather ingenious design and I'm sure it's a vast improvement over other automatic liter boxes (I really wouldn't know), but I still think those boys from MIT need to go back to the drawing board. Maybe my threshold for noise is different than others, but I find this box intolerably loud and annoying. The raking itself is loud, but then at the mid point of its direction change, the rake pivots and falls to the other side making a very loud clunking noise. This, of course, is endlessly fascinating for a kitten and he will promptly investigate the noise and end up going inside the box again, setting off the infrared mechanism, ensuring that the cleaning cycle will happen 20 minutes later. I can't really fault the manufacturer for a kitten's curiosity, but I do believe it's something kitten owners should be aware of. In addition to the noise, the rake spacing is still rather wide which will invariably lead to cat poop getting behind, and thusly out of the reach of, the rake system. Sorry, but I never had to scrape crap out of my old litter box with a butter knife. Just let that imagery float around in your head for a couple minutes. I haven't had any problems with urine leaking through the bottom of the trays, but then again, I haven't had a tray in the box for more than a week. However, I did notice that the corners to the tops of every box were broken at the seams; though I don't know if this is from how they were shipped, or a manufacturing defect. Anyway, long story short: I'm switching back to the old box once I use the last refill cartridge... so that should be in about 6 days.
Edit (1/27/08): After browsing around for a solution to the smell, I tried one of the suggestions which is to mix the litter around manually and that definitely seemed to help, though ScoopFree recommends you just leave the box alone and let it do its thing (that's what I had been doing). Someone else recommended using a small amount of baking soda on the bottom of the tray before pouring in the crystals. I'll give that a shot on the next cartridge. Anyway, taking 15 seconds out of your day to mix around the crystals isn't a big deal and if I can squeeze at least 2 weeks of use out of the cartridge, I'll definitely bump up the rating.