After doing a lot of research online I realised that for most purifiers the reviews talk about poor after sales service.
Based on my previous experience with other Philips products, I decided to buy a Philips water purifier though there were not reviews available online of the same a year ago.
We bought the Philips WP 3890 from E-Zone Hyderabad a year ago and till date it has been working perfectly. I have never had to call the after sales service since the time it was installed.
The installation process was smooth and done on time as promised. In fact, the engineer installed it in the morning and called the next day to confirm if there were any leakages etc. Since then the purifier has been working flawlessly. I think this is a great product and would definitely recommend it over an Aquaguard any day(as we have one at our home in Mumbai).