I used airtel 3g for a long time .its always working good if you are in delhi ncr zone but I have a very bad experience of airtel 3g when I go for three months in himanchal pardesh the network of airtel 3g was very weak there and I face problems there only . but in delhi I have a good experience with airtel 3 g . overally its good and airtel network easily available everwhere this is the good thing .