Cost of Cat Attract is about £27.00 ( http://www.rlpetproducts.co.uk/store/cats/litter/ ). Mixing it with another litter means it lasts me about 8 weeks for 2 litter trays. It clumps so you can just remove the clump (as does OKO). I remove clumps as soon as they appear.

I don't throw old litter when I wash out the trays (once a week). I sieve it and remove obvious small lumps.

When I was cleaning up wee it was costing me far more for specialist cleaning products to remove wee smells.

I would rather pay for the litter that works (along with diffuser) than have evil smelling carpet or wack out for specialist odour removing cleaners.