I've just done 750 miles on the premium Shell stuff - the car felt good - but that could be down to the French roads - i guess the next tank needs to be supEmarket sourced to see if i can really tell the difference.

150 to the tunnel then 2 x 300 mile legs in France with a short stop - I love that car

Just bought some BP ultimate Diesel from a garage a few miles away and is a fair bit more than my normal diesel (Esso) . I normally pay @£1.20 /litre but the BP stuff is £1.41/litre so £6.35/gallon as opposed to £5.40 , so by my calculations, if I currently do 33mpg (which is my average), I will need to average 38.5mpg using the Ultimate diesel just to 'break even', so, unless I notice some exceptional difference, it seems to negate part of the advantage of me switching from my 23mpg L322 to an L405. Has anyone else got this 95p/gallon difference at their garages or am I just unlucky with a very expensive BP station and need to look further afield for a more reasonable one? Steve

Main car : FFRR L405 Vogue SDV8
Other car : Vauxhall Lotus Carlton
Past cars : FFRR L322 Vogue TD6 SE (Sept 2006 MY07) ; LandCruiser SWB ; 4-Runner ; Supras; XJS V12 LeMans

Scrimping pennies on the cost of fuel when your car if choice is a FFRR is frankly bonkers. I use shell nitro or bp ultimate because you go further on a tank and the car runs better. Yes it's more expensive, but so is your car! I also use she'll nitro in my cooper s, with noticeably better consumption and performance. On standard petrol that car does sub 30 mpg, on v power nitro its 35.

I pay £1.33 from memory for the BP Ultimate, its more at motorway services though, but I agree that a few pence at the pump is minimal, because I really do think the engine is more refined and eager with the premium stuff. I think it helped the gearbox up and downshifts too with a more responsive engine. Don't get me wrong, its not transformed, just a little better.

Not enough for my needs (see my other thread about driving yesterday) but its still better.

Sorry Andy , don't think it's about scrimping, else why would I have bought a RR in the first place. It's just I'm very happy with the cars performance (I had the 3.0L BMW diesel in my last car so this is very significantly quicker/more powerful) and think our fuels prices are far too high so what I currently pay for 'normal' diesel, the shell/bp stuff would have to give me at least 15% better fuel economy just to break even with the normal one, else for me personally, there is no advantage (especially was I would go out of my way to get to the better fuel in the first place, so also negating part of the extra mpg I would be getting). If I can start getting 40mpg out of it, I'll put it in all the time, but from the £80 worth I put on the other week, I've not noticed any significant enough increase in mpg and nothing noticeable stood out in the performance side , but this is just my opinion. Steve

Main car : FFRR L405 Vogue SDV8
Other car : Vauxhall Lotus Carlton
Past cars : FFRR L322 Vogue TD6 SE (Sept 2006 MY07) ; LandCruiser SWB ; 4-Runner ; Supras; XJS V12 LeMans