I guess i have found a way to actually cut back on my international roaming bills. Recently i was flying to US and tried using Matrix international sim card. Was surpised when they asked me the area code for my stay and all and gave a me a tariff plan according to the same. Used the sim for a month and returned back with a total billed amount of 8k, which is 3 times lesser than what i usually pay on my Vodafone number !! Traveling and saving with Matrix is a must 