I have been using airtel from the past 2 years. The major reason being it hasbetter coverage than any other operator. The voice quality is excellent, signal quality is very good however when it comes to data, it is a disappointment. The data plans are costly and the data provided is very less. You will keep checking your data balance every now and then. However, the only relief is ( if u use internet at night) they give 5gb data free night data by completing some small tasks ( like recharging your number, playing music or games on their wync music or games app, referring the app etc) . It is a nice approach by them to keep their customers. If you are looking for the best signal quality and range, Airtel will serve your needs. However, regarding plans, you may need to look somewhere else. Also, their customer service and myairtel app are very good.