I would defo recommend Chick Crumb if you're currently using Worlds Best.
It is just as good at a fraction of the price, and even if you don't flush, its still much lighter, less smelly and of course biodegradable which has to be a good thing? To be honest, I only flush poos, wees clump so well they go into the bin in a biodegradable nappy sack ..... sorted!