Re: Not my experience
Well, I don't live in a town centre, but there is a 4G mast operated by O2 and Voda right across the street.
When I joined Vodaphone, it was because O2 were not willing to do a decent offer on a new phone, and Vodaphone were happy to beat the rest of the competition at the time.
Their slightly flaky network at the time has only improved since then, and I personally don't have any issues unless in the heart of say, the Peak District, amongst the hills, where a) I had better signal than my Father who is on 3, and b) I had brilliant reception once at the top, away from the ground clutter.
There may very well be places where Vodaphone's network isn't as good, I can't try it everywhere myself, but I have no problems with it.
Not being a shill here, but they have always done a good service for me, at a good price, and across moving from one corner of the country to two others, visits to family spread out all over the place, plus holidays here and abroard, I have very rarely been lacking in signal when others across a whole range of networks had it.
If this changes, I will be happy to jump to another provider, like I left O2, but I at least am very happy with the current state of affairs as I fit into it.
Note: I currently live in a small town in the South East, but fairly regularly go to the North and the West, and have been on holidays around Europe and Wales, The Peak district, the Lake district, along the South Coast and through the New Forest, and more, providing a decent set of data samples.