These people have a good product but they are masters in cheating the customer and change their policy(impacting customers) without any information.
One fine day you will not receive bill because you have paid them advance. They will ask you money if you want Bill which I have never seen anywhere in the globe.
They do not take calls and the call center executives are totally dumb.
The worst part is that the bills are not available at their portal as well. Not sure how can a customer know his account status?
They cannot provide the details of the usage also and if you shout at them, sometime they will reset your FUP but no back end clarity from the team.