Cons: Contains silica dust & sodium bentonite which may be harmful to your cat.
I used Freshstep Kitty Litter for many years, but would not recommend it, or any clumpable clay litter. These litters contain silica dust, which when inhaled by cats during digging or cleaning themselves could be harmful. In addition, these litters are composed of granules which contain sodium bentonite which can be ingested by your cat during grooming (granules get stuck between their toes). Some cats even eat the litter. Many owners attribute their cat's health problems to these ingredients.
In addition, the clay clumpable litter (Freshstep, etc.) gets very heavy and sticky when wet, thus making it hard to clean the kitty box.
I now use natural kitty litter--The World's Best Cat Litter--which is made from naturally processed corn. It does not contain silica dust or sodium bentonite and produces no dust when poured. Additionally, it does not get heavy (like clay) when wet, thus making it easier for me to clean the box. I have found that my kitty box smells much better with this litter. My cats had no problem with the change to a different litter.
Another natural alternative is Swheat Scoop which is made from naturally processed wheat.
If you are interested in reading articles and testimonials about the harmful effects of clumpable clay litter, please go to "Cat Litter and the Health of Your Cat" at http://www.swheatscoop.com/