The fuel cap on my FSI states either 95 or 98 ron fuel.

Presumably one can put 99ron fuel in the car instead on 98 ron.

Shell optimax used to be 98ron but it has now been replaced by V power which appears to be 99ron.

Also tesco's premium petrol appears to be 99ron.

Does tesco petrol have cleaning additives like Shell claims it has on all its petrol ranges?

Having run it on 95 ron for a while I though I might give it ago on the higher octane to see whether the higher octane gave any better fuel economy for the 7p premium in price.

That's a coincidence! Been running on Sainsbury 97, but this week got a 5p a litre discount voucher from Tesco [with

Getting very impressed with the 2.0FSI on 99 octane - I don't think I'm imagining it. Got longer run to do on Wednesday so I'll see if the impression lasts!!

filled up with the shell vpower which seems to be 99ron - seems to run better but maybe not much difference on fuel economy

Tesco's 99 is made by Greenergy apparently, which is (slightly) more environmentally friendly than other fuels. I have been running my Octy vRS (mk1) almost exclusively on Tesco 99, and when I took it to get remapped, the initial rolling road showed 190BHP instead of the standard 180, so it definitely gives an extra kick over 95/97...