I ordered a bag, seen it recommended somewhere, thought I'd give it a go. and the house smells.... pooey. It has silica crystals in it, and is of the clumping variety.
Win win, thought I.
Plus side - no tracking (could be down to the litter mat I acquired at the same time).
I previously used World's Best, but the little dusty paw-prints on my lovely purple velvet sofa were doing my head in.
Also DCats are pooing a lot more indoors (in covered litter boxes) because they don't agree with the weather, which is clearly my fault.