My local filling station is BP and their Ultimate unleaded at 97 Octane runs well in my 1999 Plus 8.
The standard Unleaded at 95 Octane runs equally as well but I think the Ultimate possibly keeps the internals cleaner reading their publicity on it.
TBH I have never noticed any difference in performance, I was advised by my MOT garage (non Morgan) to fill up with Ultimate to keep the emissions check happy so I make sure I do together with an Italian tune up.
