I make do most of the time with a Brita and I do change the filter religiously. Not sure about the impurities, but it sure makes the water for coffee tasteless. I had a guy come to the house once with the pitch for a 3000 dollar system, but didn't feel it was worth it.

My city offered free water testing from an 'independent' lab - the water was deemed safe.

If and when I do buy bottled water, I am sure to recyck the bottles.