Moving from Virgin/EE i was expecting O2 to be a little slower but they are simply unacceptable. I mainly want to use my data to stream you tube and music when on the move, not talking 4k video but I regularly get awful buffering and time out errors on the most basic apps. If you looking at their coverage and think it looks fine for your area, think again, it's the bandwidth that's the issue, their connection ratio is so appalling that I cannot use my phone in Manchester city centre. Save yourself 2 years of misery and pay a little more for a better supplier.