Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Great value and even greater peace of mind

I have been using this for about 3 weeks, and it turns my water into something I feel safe drinking. I had an ecol i scare in 2008, and hadn't felt comfortable drinking the water. This takes care of the problem and is saving me time and money, not to mention space in my garbage with all the used bottles. I'm very pleased.