I found Vodafone network connectivity very good and strong. Vodafone network charges you a huge sum of money for its services but those services worth that much money. Customer service is very poor. You have to go through a lot of process before they give your call to their executive. This irritates me a lot. They internet speed and network range is high. Dont matter its 2g or 3g you will be satisfued with the speed. They keep informing you about your data charges which is good.
Vodafone is one of the Indias largest mobile operator with over millions of users and so far got success in keeping those users within their network. Me myself have never thought about mobile number portability which is good.