I had an under sink filter with three bowls, don't remember the name. We didn't change cartridges for year and a half, but drank and boiled water anyway. Don't know why, but I decided to change the cartridges - and couldn't understand which I need to buy :) Thus I started to look for a new filter and found your site. Really liked the fact that it has no replacement cartridges and includes anti bacteria protection (I have two little kids, and really want them to drink safe water), decided to order. We are so happy with the filter, the water even tastes better!