We bought Kent RO about 15 months back and had a pathetic experience with it. After buying we had to change filter twice and RO membrane once and booster pump once.
Overall I have spent around 5000 on its maintenance. Electricity and water cost extra. For a INR 15000+ product we spent 1/3 of its cost on maintenance every year. Not great. This is a pathetic product. The first time we had to get the filter changed because its plastic case broke off in just 3 months. This shows the cheap quality of product.
P.S.:- I bought my car around the same time and have spent much lesser on its maintenance till now .