Is Shell Optimax 99ron now everywhere? I know for a while it was only some garages selling it, the rest still stocked the 98RON stuff.
I do recommend it. I ran my previous 3.0Si on it (98/98 RON Shell)for some 30,000 miles. Towards the upper end of that milage I was forced to use normal unleaded and the car hessitated on it, had a flat spot near 3000rpm if I remember correctly. As many know the 3.0 does making a pinking sound, it's even worse when changing from super to normal fuel.