Among GCC Countries qatar governments water is good.Because they use the RO process, but the condition and cleanliness of pipework and storage tanks is extremely questionable.So use UF OR UV FILTERS.Never use RO process in home,because once the water undergoes through RO Process and we again try to pass the water through RO Purifiers its TDS Value becomes below low(ie,no required minerals in it),regular use of this may cause cardiac problems.