Works very well...I used a PPM device and water testing strips on the tap water before distilling...the tap had 220 ppm (not good) and after distilling, it was only 1.After about 20 gallons distilled, the inside of rhe machine was dirty (scale from water) and when I poured water in, the water was translucent brown...but the water still came out only a 2 ppm. The water testing strip came out virtually perfect as well. I just wanted to see objectively for myself how well it worked, and am now telling you.I am using the sulfamic acid to clean it now.For a total Amazon price of $75 (tax etc) it is more than worth it.If it cleans tap water that bad, and you know water is only 2nd more vital ro breathing, its a no brainer to pay that one time small price to have clean drinking water.The boiling kills the germs if any even lived the process. Pour it into a 55 gallon HDPE drum for storage and add sodium hypochlorite preserver, and you have perfectly good water for 5 years stored.