Supermarket fuel vs independent suppliers - which is best?

Last week you advised against supermarket petrol. I have long been confused about this issue. I have been told by one chap who was 23 years in the oil industry that refineries supply to large numbers of suppliers and do not have the means or desire to improve upon the fuel supplied to independent, i.e. non supermarket suppliers and that the only differences between suppliers is what additives they may use. Could you explain your advice further please?

Asked on 29 December 2014 by Stuart

Answered by Honest John
Yes. Shell V-Power Nitro + is 99 Ron rather the the 95 Ron is standard pump petrol. And it includes important detergent additives. The net result is around 2 per cent more miles per gallon and an engine fuel system that stays clean.

V-Power diesel contains a cetane improver, detergent additive and lubricity enhancer, so it, too, gives more torque at low revs, therefore better mpg when driven properly as well as taking better care of the high pressure injection pump and the rest of the fuel system.
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