Whichever you choose, if you are moving providers, remember to negotiate price. I am on BT and came to the end of my contract. I looked around and saw that o2 were the cheapest (I have an o2 mobile contract which makes it even cheaper). I asked BT to match o2's price if they wanted me to stay with them, and they did, plus threw in the latest router for free. Don't know if you get the same wriggle room on price when going somewhere new, but it's always worth asking.