I don't know the technicalities of why it is so, but Three is the worst network when compared to EE (4G), T-Mobile (3G) and and Vodafone (3G). There is a mast within a mile of our office (which is a portacabin so hardly some lead-lined Fariday Cage) yet I step indoors and lose all connectivity to the outside world - often receiving texts and voicemail notifications several hours later.
It's a shame I opted for the 12 month rather than monthly offering as I'd be off like a shot.
As many people have said, they are great on price, but their service offering leaves a lot to be desired.
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