I dont think any of the cars were tuned.
But a lot of modern cars ECU will react to the change of octane anyway. Hence with the 2.0 TFSi VAG state it will have less performance and MPG on 95Ron over 98Ron
Just as a side. I lived in germany for 2 years. There Shell V-Power is 100 Octane. My Car (which is at REVO Stage 2+ now) has never made any difference on a RR with 99 or 100 Octane. The MPG was as near as makes no difference the same aswell.
Maybe the one that boosts the octane by 4 (so would turn V-Power into 103 Octane) would have some effect but the others i would be inclined to say are more of a Placebo effect than anything else
Just my Opinion.
Carl 
There was a test done on 5th Gear which basically proved V-Power and the likes were useless on an un-modified car.. on a modified engine, i.e. if you've manually advanced the timing (The OEM parameters will not advance to these levels) then the higher octane will stop the ECU pulling the timing back and give more power.
The benefits of 99/100 on a
stock car will be nigh on nothing in an N/A and 2-3%+ maybe on a turbo - so you'd not really notice.
Only the few will see a benefit, you've got to help the engine get the most from the fuel.
As far as I know his old R32 still holds the record for the fastest N/A R32 1/4mile in the UK... beating so called stage 2 remapped/modified ones.
