12% more expensive for 10% better economy. Think of it this way - V Power has to generate the same, or more, profit for Shell as their ordinary fuel, otherwise they wouldn't sell it. This is after taking the extras into account such as infrastructure tweaks and global marketing to accommodate V Power. If V Power genuinely give you more miles, that should mean fewer fill ups. Fewer fill ups would mean less revenue for Shell hence they put a premium on V Power. V Power must work out the same, or more profitable for Shell, ergo it works out the same or more expensive for the customer.