Spotted in the paper today - Budgens Shops have got Coke/Diet Coke on offer, Buy 2 get 2 free.
So 4x 2lt Bottles for £4.30 making it only £1.07 per bottle which is better than the Tesco deal.
Good deal if you have a Budgens shop near you, look here for your nearest store - http://www.budgens.co.uk/store-locator/find-your-local-budgens
* Apparently offers not available in Budgens Express/selected Budgens Quickstop/Budgens Petrol Forecourt stores.*