The worst litter tray I had was a few years ago, I think it cost about £20ish give or take a pound either way which in the 80’s was not cheap for a litter tray. We were on holiday in Cornwall and you know what it is like when you are away a bit more frivolous, (I didn't know I knew how to spell that). It was a new one out on the market and was an odd shape and the litter was small black washable pellets, on the box it said no fuss, no smell and other good points. They lied. When a cat did a pee it went through the pellets, through a sieve and into a receptacle. To empty it you took of the top two parts and then you had to pick it up and hold it in both hands and it seemed to wobble from side to side. Almost say like holding a sheet A4 paper with both hands and placing something heavy on it and trying to hold it straight. Of course you can imagine where the pee went, everywhere. When the cats did a poo all the black bits stuck to it good and proper and you were supposed to wash it off, ugh. The kitchen floor was also full of the little black plastic pits. It was a nightmare. I contacted the firm and they said that they could not understand my problem. So I quoted the words on the box to them and said I would contact the trading standards. Within a couple of days I had my money back and they let me keep the tray. Which was thrown away immediately. I think they must have been withdrawn, as I have never seen one since.