I've recently seen you advise using Shell V- Power because it improves performance and mpg. We don't have a Shell garage here, but we do have a Tesco station which sells their premium brand, Momentum, at 5p a litre more than regular fuel. We have a 2007 Honda Jazz CVT. It does not seem to have improved the performance and the mpg has gone down. Is the petrol different? We are thinking about going back to ordinary petrol. We are also considering a Nissan Leaf as it seems to suit our kind of driving.