I had heard of Matrix Sim Cards many times, but never got the chance to actually expeirnece their services, until recently when i was travelling to UK. With my previous experience with other such service providers, i was doubtful already. But Matrix Sim definitely took me by surprise right from handling the query to delivering the sim and finally having the sim collected from my place. Not once i had to call their customer care for any burning issues, but must say that their services were infact better than the local number that i always bought from London.