The subject of fuel grades / Octane ratings has been discussed quite extensively here :
"Black carbon deposits around the exhaust tip." See post #11

Be aware too that the Trophy may be tuned differently for ( some ? ) different world markets,
and that tune may take into account the fuels used in those Countries,
which
may be specified differently in the Owners Handbooks for those Countries.
Uisng too high, OR too low an Octane rating than what is recommeded,
can cause engine performance problems

It is an urban myth to use a higher Octane rated fuel than recommended,
but a lot of people do this, maybe once a month, or after a certain number of fill ups with "Regular" fuel,
thinking that they are doing their engine a favour by giving it "some of the good stuff" every now and then,
the myth being propagated by Fuel companies calling the Higher Octane rated fuels "Premium Grade" or similar

Best advice - read the Handbook, and put fuel in the tank according to what it says in the book !
