Tesco's 99 all the way for me and at 95p/litre at the moment £47 fills the tank - last tank 350 miles of mixed driving. There is a TREMENDOUS difference between standard 95 and Tesco's 99 - you can hear it for a start, much mor responsive, holds boost for longer, my car has a strictly Tescc 99 only diet, I have tried V Power and it is not as good guaranteed. My local Tesco's has a small problem with 99 in that it is not always available there, but they do get deliveries often - suppose thats good as the fuel isn't in their storage tanks long enough to for the RON value to start depleting.
Regards,
Gareth