I am a user of Xiomi mi4i since last 1 years, without any instrumental problem. Nice phone with attractive look and light weighted. Camara quality is very good. Only minus point is, it has not exlandable memory but mi account provide cloud backup of 3.5gb for backup. Battery backup is also very good. It has very nice feature which is prevent pocket call and another is second space.
Now come to Service centre, very worst experiance at service centre ( visited at park street, kolkata) never think such a renowned brand can have these type of service centre.