Dan_Musicant wrote:

Myself, I've been using the cheapest regular I can find, usually from
Costco, or a station I know where they sell pretty cheap if you give
them cash. I drive less than 2000/year with my two cars, so it isn't a
giant deal for me, but more mileage and smoother performance would be
reason enough for me to switch to a recommended brand.

to me, there are 3 tiers of gas...

the full price, like chevron, 76, etc.
the discounters, like costco, sams, vons
the unknown mom n pop places.

the discounters have a reputation to uphold, so their stations are
generally clean, and they still have a good price. i just dont trust the
unknowns. yes, they all get gas from the same sources. but who knows
when the mom n pop places replace their gas pump fuel filters, etc.