I have distillers and I use them when I make colloidal silver. They are not good for drinking water though because they remove all the beneficial minerals as well. The water is not healthful and tastes bad.

We researched it thoroughly and, all around, the Berkey was the best solution. Removes heavy metals, chemicals and fluoride, while leaving the beneficial minerals. It's expensive for the outlay, but cheaper than bottled water in the long run.