Hi folks, we are going to London and SE England for 3 weeks in August and as i am an old fellow and don't know too much about phones and computers i am asking which is the best sim card for us. We will be staying near Heathrow and touring Kent, Sussex & Hampshire as well as a few days in Derbyshire. WE will not be making any international calls and probably not so many local calls. Thanks for any information on which sim to buy.