We use Swheat Scoop, and have been very happy with its performance. Considering how much longer that litter lasts (without being stinky at least) and that its lower dust and healthier for yourself and your kitties (and the environment for that matter), with the bonus of being flushable, its a great excuse to upgrade.
A recent addition to our Petsmart has been Excuisicat (or something to that effect) litter, which is available in paper, corn, corn+pine, pine, and wheat from what I saw at a lower price than Feline Pine, World's Best, and Swheat Scoop and might be worth some research.
