I know millions others have asked this question but I do have some specific needs that need your expert advice please.
I'll be arrivign Heathrow in a Sunday morning about 6am. I'll be collecting a car and drive through London to Lewisham. I have an unloacked phone but there are about five devices between the three of us. Ideally I want a SIM card with some talk time (may be 200 minutes in all) and ideally unlimited data with tethering. I'll in the UK for about 13 days travelling in greater London area, M4, M5 then Exeter/Devon/Cornwall. So in short, I need a SIM card that has some talk time, unlmiited data, allows tethering.
I searched around and found the 3 with a £15 get me all these but not with tethering. I though Virgin with the same package allowed tethering but their website says not (and also it says it will only give 3G data not limitied after July).
The last time I did that Heathrow/Lewisham journey was 16 years ago so if I have Google map with me all the time I would feel safer. Given, however, that it is so early in the morning and people have advised against getting the empty SIM card in Heathrow (if I get that from a vending machine, how do I top up to get the unlimited data?), what would be my options? Carphone Warehouse and Phones4U don't open until 10 or 11 on Sundays. Can I get SIM and top it up at Tesco or Sainsbury (assuming they open early on Sundays and have the Phone shop - do they have people in the Phone shop that can confirm the SIM features I need?)?
Sorry, so many questions but would be grateful for advice please.