Not cost effective
A single bag will fill maybe 2 big litter trays, and as litter is non-clumping it will need changed after a week or two....
It does not work well if mixed with another litter, the crystals dont change colour.
Lastly, the crystals are multicoloured, with most being white, but that makes judging if your cat is urinating blood quite difficult, if most crystals turn yellow but some are off yellow/orange/red, the examples on katkin website do not reflect a real life urine example