Re: Regular v premium
As a side note to your inspection thoughts, I used to mechanic for a taxi fleet up north and we had a specially built carb from an old school master mechanic we would use to pass emissions. It was jetted SO LEAN the exhaust manifolds would be glowing red hot within about 10 minutes run time.
Never failed a test using that carb, even on motors so badly worn they were smoking like a bug fogger with normal carb. Bad valve seal, excessive blowby, didn't matter.
We had to start the motor with ether due to the insane lean jetting, but once running, it WOULD pass.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.