Thanks everyone, it does seem as though Vodafone is the one to go with. Will contact Ofcom, Jim, and ask them as it's a lot easier than scrolling around the country on their website, interesting as it is to compare the providers. And have checked, and seems I've already registered my number on Emergency SMS so that's good.
As mentioned Vodafone have great signal, but they are the most conning ever. I have SIM only on vodafone, I give them as little as possible.
Off topic I moved my daughters phone away from Vodafone to 3 network because of Vodafone data charges, she has been using the phone the same if not more on 3, yet 3 working out her used data is over 50% less than Vodafones. This makes me wonder how Vodafone charge for their metered data has OFCOM tested this, probably not.
Just saying before you get involved with Vodafone, what to expect!