I have been account with zerodha for around four month back and my experience with zerodha is quite amazing as it has zero brokerage which is my requirement and there are not any hidden charges. Their customer care service is quite good, their CUstomer relationship manager ensures that any concern should be resolved as early as possible.He is the main point of contact.
Website is very user friendly, you can easily get what you want. Website is safe and secure and its take very less time to open.
Its really a good website.