I had heard a lot about matrix SIM cards from my friends so this time decided to use their services instead of carrying my Bangalore number to London. Good first time interaction with their sales guy Rahul. He explained the process clearly of how it would be charged on the card and so on. While in London the only issue that I faced was the first time when I changed my sims, it lost connectivity for almost an hour. I have to say that matrix has very good turn around time to attending to issues because within a few of my email, I got a revert with the settings for international dialling. Followed those and worked fine after that. No issues for the 15 days that I used it. Overall good experience with them. Thanks guys