Reliance offer is for people who is one step behind getting a mobile phone, of course it doesnt mean exactly for those.the current gsm handset can be exchanged for international talktime but I dont know everyone has a relative abroad.also if making a call is cheaper why bothered about the sms.gsm cellular is waking up by shaking hands each other.in national roamimg they are providing signals not only with their partners which was old story now whichever signal is available the handset will automatically select the service where the service provider is good enough.so I can tell one thing where time only answers it