I was in Germany for a project and for those 3 months i had used the services of Matrix International Sim card. The only time that i remember calling the customer care was when i had landed and my sim wasnt registering any signals despite several efforts. But with the instructions, it sure did work within an hour. Also since my office was paying the bill, even i had asked for a copy of the same which they always obliged on time! So basically Matrix on service standards is at a score of 10 !!