Trust me I've spoken to members of their customer services team as well, and they're all sticking to the same line. I do know my rights in this instance, I've even had written confirmation from the OFT via their Consumer Direct advisory service. The truth is though that if a store manager is determined to flout the law, there isn't much you can do there and then. So I've fired off letters to Trading standards and Consumer Direct as well as Jane Hext (Vodafone's customer services director).
I'm just saying if you don't want to go through all that, don't buy from a Vodafone store.