[acshortt5]

Having worked at various petrol stations I can vouch that the supermarkets indeed get poorer quality fuel, by the sounds of it Tesco's appears to be worst. Companies like Jet and Esso are generally fueled by Conoco who refine their fuel to a better quality (more additives) Shell & BP of course do their own fuel which is refined even better. Most of the supermarket fuel comes from the continent and generally doesn't get as well refined. We recently had a crisis in the south east (I'm in Peterborough) where silicon was found in petrol. Suprise...it was just supermarket fuel which was affected (and not just Tesco's!)

Regarding the vpower I put a tank in my s70 t5 and while it gave a little bit more performance economy went down. (maybe due to my enthusisatic driving). I find BP ultimate very expensive to say it is only 97 RON.

The best compromise I have found so far is either shell regular fuel 95 RON which gives fair performance for a decent price or Jet Super 97 RON which gives really good economy and decent performance.

Hope this is useful.