I've changed over to the World's Best Cat Litter (yes, that really is the name of it.) I love it because it really absorbs odor and liquids extremely well and when it's not nearly as heavy as the clay mixes.
http://www.worldsbestcatlitter.com/
Testimony - I had this at a 50% mix with the clay stuff. I left for a week for my grandmother's funeral; a friend made sure they were fed. (I told her not to worry about the boxes). When I came back, I did not smell the boxes until I moved them to completely empty the pans & start over.