I use the World's Best (original) and I love it! I definitely do not have a tracking problem and even though Max has very furry paws and paw pads, I have never had to clean any litter off them. I even carry my own litter to the shows instead of using the litter provided there. I figure Max is used to the World's Best and I don't want to confuse him. The only issue I have with it is cost, but with only one cat, it isn't a big issue. Also, the company has a Frequent Buyer Program (explained on back of bag), so after so many purchases you get free coupons toward your next purchage. Even in regards to expense, it clumps so well, that it when you scoop you really are scooping everything that smells and the box doesn't seem to have to be changed out as often. It also never gets muddy like clay scoopable litters do. They say it's flushable, but I have never tried flushing it. Here's a site where you can read a bunch of reviews of it:
http://www.viewpoints.com/By-nature-Worlds-Best-Kitty-Litter--23522-reviewsMax was litter trained using scoopable clay litter and so the night I brought him home, he didn't seem to know that it was okay to go in the new litter box (with a new kind of litter.) That night, I replaced the World's Best with scoopable clay, but as soon as he went, I scooped what he did, replaced the clay litter with World's Best and deposited his "deposits" back in the box. From that moment on he got it and we've been good to go.
Kris