Hindustan Unilever Pureit Marvella RO has advanced RO technology which provides absolutely pure water with its 5 stage purification process. It has advanced Alert System which I think was first of its kind in India and gives you 15-days advance warning before the RO membrane shuts off. When we were to buy a purifier 4 years back we were to make a choice between Kent and Marvella.
In kent the whole machinery is visible from outside and doesnt look nice. So we opted for Pureit Marvella. Though its a good product and has a good storage capacity of 9 litres I must mention its maintainance cost is very very high. You have to spent Rs.3650 for getting the RO kit replaced and this is a half yearly phenomena in our case.