Total dissolve solids are in water with is not suitable for drinking, If TDS rate is high it means impurities is available in water and can not use.The pureit products does not provides RO Water in this model but in cheap rate it purified water satisfactory.Most of people can not afford the unit purifier for RO water because it will be costly for them.I suggested those people can not afford RO Unit, avail pureit classic model in cheap rate and prevent thier family from polluted or contaminated water.Most of disease occurred to drinking polluted water at all.I suggessted them to use pureit filtered water.Keep filtered water in bottle everywere you walk.It is neccessary for all.Do not use water in restaurent or road side hotel.Finally, I can say that FILTERED WATER IS GOOD FOR HEALTH WHICH COMPENSATED BY USE PUREIT CLASSIC MODEL.