The Japs do not have west Texas water so hard you could almost walk on it. The mineral content is so high it coats the heating elements on point of use systems, the efficiency goes down and they require de-mineralizing quite often. I have several friends who bought the BS and they all say do not get one.
Now, I suppose they would work with a whole house RO installed but the cost is prohibitive for us plain working stiffs, so a natural gas old fashioned water heater is about our only choice and drain the heater once a month works about as good as it gets here.
I always say to enviros that complain we use too much bottled drinking
water and tap water is just fine to come on down and I will show you how good our tap water is. One swallow and they are reaching for Dasani bottles.
BFL