i have been running a Civic Tourer I-DTEC 1.6 for the last two + years and have always used premium diesel in the belief that that it gave me better m.p.g. And was better for my engine. As the car is now going and being replaced by a new CR-V 1.6 I am wondering whether it is really worth it. I know that the arguments rage on about the perceived benefits of premium but I have to say that I a not convinced and any evidence seems to be anecdotal with no concrete scientific justification given for the increased cost of the fuel versus the benefits. I have looked for a thread but have not found one on the site ( that doesn't mean there isn't one, it just means that I am thicker than usual) so come on, what can be said to justify the extra expense or otherwise!