I use cheap Clumping Litter on sale. $6.00 CDN for a 20 kg bag - that's about 50 lbs. My cats have always used it and I'm afraid to change now. Sure it's dusty, but I just dust more often. Sure it isn't flushable, but I just double bag it and put it down the garbage chute every day. Works for me. If you scoop often enough, there is very little smell.