I aM using this aircel sim card from past 5 years the network coverage in mumbai is good but as u move outside the city it starts lacking no range in village side
What I like is internet pack of 2g which van only be used chatting purpose mostly in Rs 24 you get 100mb for one month which is much better when ever am out of house or office I use it for chat other times wifi is usefull in office and at home
As the service centers are good I got my sim updated on the spot
Customer care is bit hectic you need to call serval times to reach for prepaid demartment then complaint department an all
Other wise you will rech to post paid department while your using prepaid sim