they don't have good service coverage. the online map shows it has full coverage but the reality was one bar of 4g in central London and in zone 2. Would regularly have zero bars. Totally weak. I had a conversation online with support to ask if I was able to leave, having been ported to them for a couple weeks and the person just came back and said "service will terminate in ten minutes". Thankfully it was easy enough to go back to O2 and a good deal from them.
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