Ok, I tried the backyard distilled ethanol free premium/super gas in my mower. It went from running ok-ish with regular gas to running quite smooth. The Honda engine on my mower has a design flaw with the automatic choke. With normal gas, it adjusts itself too wide and the engine starts, but it dies, regardless of air and engine temperature. To fix that, the previous owner and myself had to limit the auto choke with a paperclip to prevent it from going fully open. This worked, but it wasn't ideal.
Now with this nice ethanol free gas, I couldn't get it to start with the modified choke. I removed the paperclip and let the choke go full open and do its thing. Now the engine starts first pull and runs very well. No misses or surging. No pinging (I would hope so!). RPM is the same. I'm not sure if it has more power, seems to cut about the same. But it sounds really good. The choke thing may have to do with the pure gas having more energy per volume, requiring less choke and more air intake.
I made about 1.5L of this which was a bit much. So i just put the rest in my other mower that has regular 87 octane gas. I'll be able to test the fuel economy the next time I fully mow my front yard starting with a full tank.