Alright, this is somehing I know alot about.
Fuel pumps. The government tests the volume of fuel pumps once a year. They place stickers on the pumps that is unlawful to remove, you may have seen them, they say +1, +2, 0, -1, -2 and so on. In some states at +/- 4 they pumps have to be recalibrated and that is costly so the station owner will wait until it is at the very end of the spectrum. Look for the pumps that have the pluses, thats how many extra ounces of fuel that come out when the pump registers 1 gallon. If you have a v8 SUV your always on that ball. For a 6 gallon bike it doesn't save that much.
Now for the octane thing. 95 percent of the gas in this country comes from the same pipeline distribution network. BP is about the only chain that still houses their own end stations, but still sells to other operators.
Those octane ratings can get kind of tricky though, because fuel trucks only carry two types of fuel (besides deisel), Unleaded and Premium. The mid grade is a combination of the two and for that you have to trust the truck driver to mix it appropriately. And into a tank that someone else guessed at. So, fair warning about mid grade. All or nothing for consistant octane delivery. Personally, I use 91 when it's available, If I'm looking for midgrade I'll fill half and half from 87 and 91.
Cudos and happy hunting for the off calibrated gas pumps.