Hi friends now a days I am using vodafone sim. It is good for calling because beacuse is alot of offers you have to chose like you can make your call rate cheaper than other networks and by dialling easy number you can easily find your offers, but I am disappointing with my vodafone network when I am using 3g. Guys I always recharge my mobile with 3g offers buy some times it gives me the speed of 2g. like if I recharge my mobile with 2gb data of 3g then after using 1.2gb it gives me thespeed of 2g. I don not know why, although I read full plan after activate my data plans. Sometimes in the night when I need its speed for working then it disappointed me and I had to go to cafe for internate work. So what is the advantage wheather you have data in you mobile or not.