Around mid-2018 when my old water purifier conked off, I went for a RO Water Purifier (Livpure Pep Pro++) knowing that the water from RO tasted sweet to your tongue. However I hadn't done much research on water purification techniques and water quality of the supply that I received in my Mumbai home.
Background:
From around early 2018 the activities around water conservation and ground water recharge had increased in India. In addition to that the Indian Supreme Court introduced a ban on RO Water Purifier systems setting a baseline on the TDS parameters which should be considered before deciding to buy RO systems - https://www.financialexpress.com/india-news/ban-on-ro-systems-to-continue-in-delhi-supreme-court-declines-to-stay-ngt-order/1772112/ . The Supreme Court ruled that you need an RO system ONLY if the TDS is greater than 500 mg/litre (500 PPM).