I've been with them since 2005. The network is generally good. A few patches, as you might expect from any network, but the last time I had that problem was in rural Wales - I just fell back on to the Orange network, which was handy.
Customer service is what it is. The only big problems I've had have been with my Android handsets (first the Hero and now the Desire). I've always managed to speak to a person within a few seconds and can't think of when I experienced a queue with them. As has been mentioned, the call centre's in India, so expect long-winded scripts and being treated like a simple child. That aside, they're friendly and can eventually be helpful in getting things done. Personally, I'd prefer to pay just a little bit more on my bill to enable me to speak to a UK representative who has the power to do things on the customer's behalf straight away and respect's the customer's level of technical knowledge.
A friend has just started on the One Plan. When he signed up for it, I was sceptical that the data allowance was genuinely 'all you can eat', but we hammered it for a couple of weeks and got a good few GBs out of it. Definitely a bonus, if you use data a lot.
I pay
