I use Vodafone as a secondary number but that doesn’t mean it is second in any way. I do a lot of travelling so I took a Vodafone connection because my primary cellular operator’s coverage is not as good as Vodafone’s. In my experience Vodafone has the largest coverage area in India.
I was recently in the southern India and I found out that my primary cellular company Idea doesn’t have coverage in a lot of places. Whereas, Vodafone hardly experienced any issue. I only want enough coverage for me to make a phone call and if any company is not able to do it then it’s time to change the operator. Vodafone has decent monthly plans for both calling and data usage and actually it is cheaper than Idea cellular.
I also hardly experienced any billing disputes with Vodafone and once or twice when I disputed a charge the company waived those off. Vodafone is always a safe bet to go for.