As pointed out by others, octane levels is really about the resistance to early detonation, to put it simply, which is why (traditionally) high compression engines required higher octane fuel (higher pressure = higher temp = tendency for fuel to self-combust). Many believe (as I used to) that octane will offer higher performance. This is false. Your engine is tuned/optimized for a certain octane rating and that is good enough; the only caveat being any "engine cleaning additives" that tend to get added to higher octane fuels if you believe the marketing hype.
Ethanol is another thing altogether. Our engines (the 500s at least, and for the CBs for sure) are built to accept up to 10% Ethanol mixture (EDIT: I believe it's 10%. Could be 15%. I don't have my manual handy to check at the moment) however, it doesn't hurt to avoid it altogether. Up here in Canada, in these parts at least, that usually means Shell 91 V-Power if you want to be sure. Here's a handy site if you want to do your own research:
https://www.pure-gas.org/
Note: The site claims that Esso also provides ethanol-free mixtures at the high end but I've seen differing opinions on this so if you want to be sure you may have to do your own research on a case-by-case basis. Shell actually has an infographic on their pumps denoting the ethanol breakdown of each of their fuels which is smart and handy. I have not seen any such infographics on Esso pumps.
Hope all of this helps! Happy and safe riding!
Bert