I just use regular unleaded from Tesco, not the 'fancy' stuff. Mainly cos its closest to me and on my direct route to work. Is it cheaper than most places? Yes but asda is usually cheaper. The 5p off a litre promotions they do (that others do now) are also a benefit. I only drive 3 miles to work so my fuel economy isnt gunna be good cos of the constant short trips, but on the plus side a tank still lasts me weeks ;-)
Stuart do u remember Ormi mentioning on FB that additives are what 'water down' the fuel? ;-)