Clay SIM cards worst possible--- I have had the most sick experience of my travels using a clay international sim.. Everything was hunky dorey when they came to sell the SIM card. I bought a SIM card for Australia. I was told that the network is excellent and there won't be any issue with the sim. Everything was a sales pitch. When I inserted the sim to make my first call, it said I need to clear my previous dues to continue services! It came to me as a shocker! I dropped in emails, as I cudnt call the customer care and they kept on saying they will take is matter on priority. After 4 days I got the sim working with an email that ur issue has been resolved. By that time I had bought a prepaid number locally and was happy using it. With this experience I will let everyone know of their pathetic ways of servicing people