By "premium" I presume you mean 95 RON from a major brand and not a supermarket.

Only time we use a branded filling station is when we are on holiday, no supermarkets within 30 miles. No car we have owned has run better and done more mpg than it does for the rest of the year when using branded fuel.

All fuel meets the BS required, the only difference is the additive package and many believe branded fuels have better additives. But there is no actual proof of this, as far as I am aware no brand has ever declared what it adds and no one has proved one additive package is better than another. Its all blond totty in white lab coats.

I will continue to use supermarkets just like I have since the mid 80's. Mainly Tesco and Asda.

Hi My CRV is Just 3 years old.

I use supermarket stuff in my Mazda CX-5, but I do add Miller's Ecomax, as I have done with all my cars for the last ten years or so.

No idea whether it makes much difference, but the car has started to produce a little more power since I took it over, to judge from a particular incline that it will now manage comfortably in fifth gear.