I've mentioned these on a previous forum. Popped into my dealership today to get some spare wiper blades (£56 in case you were wondering how much) and saw a leaflet. I asked the part guys about these additives and he stated they should added to every tank of fuel. The cost of these additives were £13 - so quite a bit of money.
I scanned in the leaflet for your information in case you have not seen it. I've decided to stick with premium diesel which supposedly has cleaning additives in anyway (presumably better or more than standard diesel?)
