It’s all well and good looking at the performance, but the critical thing here is damage, cracks between valves, etc. Only time will tell with this, and most of the vehicles in “this class” attract those who always look for more, and perhaps it is those that should look into the better quality fuels.
The Ethanol reduces the pre-ignition point, but produces less energy. I have read that Tesco 99 momentum produces more power than V-power due to the Ethanol content.
It really needs to be looked into more. I would say that you should be able to achieve the 347Hp / 350 Ps on a well maintained (or even correctly maintained) stock setup.
Does anybody know if / how the RS detects pre-ignition?