Bought the PC600 about a month ago. Had the unit installed by a plumber- most easy and smooth installation. Almost immediately we could taste the difference in our water. Prior to the installation of the unit our water had a earthy/mineral smell which disappeared immediately we also noticed the difference when showering especially when washing our hair. Friends tried our water and they also noticed the difference- they though we were buying spring water. A wonderful product we would recommend it without hesitation.!!!! Buy this great product it will make your water taste like spring water. Final note the optional installation kit made the process of installing the unit a breeze.