how much cheaper is gas @ no-name stations compared to the big named ones? so would some of you say instead of filling up @ the big name companies with 89 octane, it's better to fill up @ no-name stations and get 91 octane? for the same price?

 

^it depends where you are filling up and when.
ill compare it this way from my own experience:

in toronto major gas stations are at 90.0 that day
in waterloo where i study major companies itd be ~86.5
in waterloo at a no-name gas station ~86.0

normally you see atleast 0.2 to 0.5 difference, doesnt mean that much, but the $3-$5ish every tank adds up over time