Im a aircel user operator the sim service is quite good, internet is not so good talking about 2g I have not expericienced 3g yet using wifi. well guyz I would like to share u something many users will be facing problem of extra money going while talking to someone means outgoing for eg- if utalked 10 sec 15 paisa or 20 paisa goes. here a trick im showing go to network setting select manual network aircel mumbai. Its done now u will be paid 1p/1s almost it does. try once