I purchased 3g Data Card

I purchased 3G data card.You know 3G Data cards are meant for accessing internet and emails at anytime and from anywhere.It make us free from messy wires.It provides internet access at mega fast speeds.I got BSNL 3G data card, but during the working it is offenly disconnected.It has low coverage Therefore my work is suffer.When i purchased it,first time it provided me better speed in Mb/s for download. but after some days it  gives me speed somewhat in Kb/s.i am unable to use Internet access properly because there is no Network coverage.It disconnects so many time.i am fed up with this.i did not find it satisfactory at all.so i am planning to use  reliance 3G.Its a little expensive but its connectivity is very good and no network problems.