Concerning octane,
BP usually puts higher grade fuel in their premium / 93 oct fuel pumps.
Using these fuels, your vehicle may actually run better (no ethanol crap in there).
So not because of 93 oct, but because of the higher grade fuels, I'd recommend you BP premium fuel, try it out, check to see if you notice a performance increase, which you should see. MPG wise it's not that much difference. Perhaps less than 10MPG difference.