Thanks to SP for the link and to ogb, ArfurB, HFG and Karey for your opinion
Unfortunately the first paragraph doesn't make sense to me
It is not possible to use a different home network, even to make an emergency call (even though your phone's handbook may tell you it is!).
and the info doesn't tell me one way or the other which provider is best. It states that where one provider will have good coverage another may not and vice versa so no real conclusive answer.
if you count my sis then that's 4 who recommend 02, so maybe they are worth a try. What's worrying me most is with T Mobile (my current service provider) I am on a very old tariff that doesn't exist anymore but suits me, I never make phone calls from my mobile, can't afford to, and don't top up very often for same reason but my texts cos me 10p per page and I don't have to pay to listen to my voice mail. With other tariffs,and other networks, it's more money and a charge for picking up voice mail.
I'm well annoyed that I can't get coverage in my new home from T MObile, and more annoyed at the attitude of the advisor, she didn't seem the least bit interested that I can't get a signal and didn't even try to keep me as a customer, I've been with T Mobile for years. Obviously I'm not paying enough money to warrant an apology never mind getting their interest lol
Thanks again everyone, I do appreciate your help.
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Does anyone know how much it would be to unlock my phone, if it's locked, so I can use another network's sim card (something I had no idea of til I read the info in that link)