Well you should - most modern 4 stroke outboards are basically car engines and I believe the Verado is also based on a car block.
Higher octane will help most engines if they are set up for it but many other factors to take into account - for example compression ratio etc.
Used top be the case that you could buy 5 star petrol - think it was about 105 octane!!!
Despite what most people think proper leaded petrol has NOT been banned - just restricted supply. Ther is a British company still producing it - and it's nearly 100 octane - that's what you need for your Aston!!!
Still wish I could get hold of some petrol from WWII - Spitfires ran on 150 octane stuff............